Alex & Keith 72 Monte Posted November 8, 2022 Share Posted November 8, 2022 1st a quick thanks to all the MC experts in our Group!! two Questions - a buddy did a restomod on his 70 SS Chevelle and gave me his instrument cluster to replace my standard 72 Monte cluster. I had intended to swap it out so I can remove my column tachometer. Not sure what I have in wiring as my column tach has three wires and here is what I have on the SS tach. (Photo) second question - if I just replace the indiot lights for temp and amps - wires hook up for the just the same? Thanks, Keith Quote Link to comment Share on other sites More sharing options...
1970mcss Posted November 8, 2022 Share Posted November 8, 2022 If you change the lights out for gauges you will need a different printed circuit. They should be a brown wire that runs to the coil. I'm not sure if that's all you would need. Someone else will chime in. Good luck with the upgrade. Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 8, 2022 Share Posted November 8, 2022 1 hour ago, Alex & Keith 72 Monte said: 1st a quick thanks to all the MC experts in our Group!! two Questions - a buddy did a restomod on his 70 SS Chevelle and gave me his instrument cluster to replace my standard 72 Monte cluster. I had intended to swap it out so I can remove my column tachometer. Not sure what I have in wiring as my column tach has three wires and here is what I have on the SS tach. (Photo) second question - if I just replace the indiot lights for temp and amps - wires hook up for the just the same? Thanks, Keith Hello Neighbor! I see you are in Kennesaw, I am just East of you in Roswell ! I did a similar swap many years ago and although I cannot recall the specifics I recall that in order to make the swap there are a couple of wires that need to be repositioned at the fuse panel engine harness junction if you want to run the factory circuit panel / circuit board from gauge equipped cars. After that it is all plug and play I think. Thinking back the change was as simple as "move wire X from position 1 to position 3 and move wire Y from position 3 to position 1. That description is based on a years old recollections but it really was a simple task. The specific info is out there on the net in various places and I believe it is in an Archive area on www.chevelles.com. I have long since changed out my gauges to a resto mod sort of vibe since I did what you are planning otherwise I would be able to give you more info just by crawling under my dashboard. FWIW here is the dash as it sits today..... 3 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 8, 2022 Share Posted November 8, 2022 I had some time this morning and started looking into this, maybe just to verify that my memory still works? Anyway there was a drawing that used to be on the web in several places that mentioned changing wire locations at the firewall connector. Can't for the life of me find it today. I can see it in my head but the detail info it contained.....can't recall all that. It has to be out there somewhere but I have yet to run into it. What I did learn.... The 1972 wiring is different from both the 1970 and 1971 MC's in several places. You cannot plug and play your existing printed circuit for a non gauge car with the gauges your buddy gave you. You gotta get the correct printed circuit for the gauges. Some threads on various boards indicate that harnesses under the hood need to be changed also. Look at the attached. It is a post by a fellow named Donny at American Autowire. This is Chevelle data but it is applicable to MC's Just wanted to give you a heads up here. The dash harness from your sweep dash will NOT work and cannot be made to work. It is 100% different in construction and design from the SS gauge dash harness. Even the standard dash harness for the SS cars with round pods and warning lights is different. While similar looking, there is also a common mis-conception that the 70-2 dashes are the same. That couldn't be further from the truth. Aside from the color of the numbers and letters being different (green vs. white), the harnesses on the cars are also very different. When compared to a 70, the 71 is somewhat similar, but the 72 is not even close. You will also need to change your front light harness as the wires fro the amp meter are spliced in parallel to the charging circuit. You cannot just "add" amp wires as there is no external shunt in the system and the guage is manufactured to read the current over a given length of wire. The GM documents tell you right on them to not change the length of the amp meter wires in either the front light or dash harness or the gauge will not read properly. Also, be aware that the aftermarket gauge set available has the amp meter wound backwards and when you hook it up to a new harness the gauge shows a discharge instead of a charge. Hope some of this helps. Not sure this helps or discourages you but "knowledge is power" as the saying goes. Quote Link to comment Share on other sites More sharing options...
Alex & Keith 72 Monte Posted November 8, 2022 Author Share Posted November 8, 2022 Ray incredibly helpful! I’ll have to I’ve this some thought and the good news at least I’ll be able to swap out the gear indicator (which had been broken on my automatic) from the SS cluster. Moving closer to having her on the road and will see you at some car shows! Keith 4 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 8, 2022 Share Posted November 8, 2022 I save everything, the issue is finding what i save. I found a hardcopy 4 page document on just this topic that I had printed off years ago. Now that I know the exact title.... after dinner I will see if it is online somewhere then get you a link. It diagrams the exact pin locations of the connector that connects the dash harness / engine harness to the PCB. You can pinpoint exactly what wire in the harness operates what instrument on your dash with this disertation cthat I have located. I am now questioning my earlier statement about a different PCB for gauge or non gauge equipped cars. It seems there must be two different PCB's but I am just not sure. Should be easy to look at what the usual suspects offer for PCBs and go from there. You are gonna have to change the temp sender for sure but I believe the fuel sender is the same for gauge / non gauge dashes. Car looks great very nice paint and sheet metal. Attached is a pic of my rattle trap. It has been in the garage a long time while I did work on my house and work on the driveline in the car. I really need to get it running and cleaned up. Stand by for a link later tonight.. 3 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 Do a Google search on " 71-72 Chevelle & El Camino SS Idiot light to gauge conversion" . That should get ya a PDF file with 4 pages. Let me know what ya think. Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 Typo......."70 - 72.............." not "71 - 72.................." Quote Link to comment Share on other sites More sharing options...
Michael Boyte Posted November 9, 2022 Share Posted November 9, 2022 Dang nice rattle trap as you put it !! I certainly would like to have one just like it ! Very nice setup indeed 👍 Quote Link to comment Share on other sites More sharing options...
jft69z Posted November 9, 2022 Share Posted November 9, 2022 This page from the American Auto Wire kit shows the difference in the pinout location of the PCB connection. Wire color may not correspond to factory, but it still shows the correct locations. 92972887 70-72 Monte Carlo 2nd Design Web Instructions 0.0.pdf 3 Quote Link to comment Share on other sites More sharing options...
Alex & Keith 72 Monte Posted November 9, 2022 Author Share Posted November 9, 2022 Joe - thanks so much for the diagram! Most helpful. Ray - Great looking big block and Monte! I’ll google too the subject you mentioned. Happy Motoring Gents! Quote Link to comment Share on other sites More sharing options...
jft69z Posted November 9, 2022 Share Posted November 9, 2022 26 minutes ago, Alex & Keith 72 Monte said: Joe - thanks so much for the diagram! Most helpful. Ray - Great looking big block and Monte! I’ll google too the subject you mentioned. Happy Motoring Gents! You're welcome! Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 56 minutes ago, Alex & Keith 72 Monte said: Joe - thanks so much for the diagram! Most helpful. Ray - Great looking big block and Monte! I’ll google too the subject you mentioned. Happy Motoring Gents! The diagram that JFT69Z provided is the same as the one I referenced with the exception that there are some changes / differences at the firewall connections which are outlined in the doc I directed you toward. You are gonna need those changes also. I think you have all the data ya need now! There is soooooo much info out there but for better or worse it gets lost in cyberspace. Some of the message boards like Chevelles.com have sections that are "libraries" for this sort of info but even then it can be a lot of searching just to find the board with the data. Staring into my coffee this morning and had a thought...we can't be too far apart given Roswell and Kennesaw as the locations of our homes. How about a cup of coffee some morning? Ray Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 11 hours ago, Michael Boyte said: Dang nice rattle trap as you put it !! I certainly would like to have one just like it ! Very nice setup indeed 👍 Thanks for the compliments, "peer review " can be very rewarding! Projects with the car seem to take longer now than they used to and the car sits more than I would like, don't drive it enough 'cause I am always tinkering. The tinkering always takes longer than I planned. Gettin old is NOT conducive to ripping thru projects on the car like I did when I was younger. Quote Link to comment Share on other sites More sharing options...
jft69z Posted November 9, 2022 Share Posted November 9, 2022 43 minutes ago, LS65Speed said: ... is the same as the one I referenced with the exception that there are some changes / differences at the firewall connections which are outlined in the doc I directed you toward. You are gonna need those changes also. Here is the document Ray is talking about, in case someone else needs it. Idiot light to gauge conversion.pdf 2 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 2 minutes ago, jft69z said: Here is the document Ray is talking about, in case someone else needs it. Idiot light to gauge conversion.pdf 85.11 kB · 0 downloads That is it. For some unknown reason I had trouble posting a link to that document ????? That is why I posted just the inquiry string I used in Google. Quote Link to comment Share on other sites More sharing options...
jft69z Posted November 9, 2022 Share Posted November 9, 2022 15 minutes ago, LS65Speed said: That is it. For some unknown reason I had trouble posting a link to that document ????? That is why I posted just the inquiry string I used in Google. I just copy/pasted what you typed, corrected it to 70-72 as you posted later & it came right up at the top of the google search as the .pdf document. The link itself appears to be below, but it just downloaded automatically when I hit the search page result: https://www.chevelles.com/attachments/idiot-light-to-gauge-conversion-pdf.728258/ 1 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 9, 2022 Share Posted November 9, 2022 42 minutes ago, jft69z said: I just copy/pasted what you typed, corrected it to 70-72 as you posted later & it came right up at the top of the google search as the .pdf document. The link itself appears to be below, but it just downloaded automatically when I hit the search page result: https://www.chevelles.com/attachments/idiot-light-to-gauge-conversion-pdf.728258/ My issue was pasting the link to FGMCC. For some reason after I pulled up the PDF then highlighted the URL in the browser window I could not "paste" it to the response area on this thread. Didn't just wanna fool with it so I just gave you guys the text for the inquiry. Patience is another thing that fades along with stamina as we get older. Some who have known me for years and years would say I was never patient and that might be so but one thing is sure I am not getting more patient as the days pass! LOL Quote Link to comment Share on other sites More sharing options...
jft69z Posted November 9, 2022 Share Posted November 9, 2022 28 minutes ago, LS65Speed said: My issue was pasting the link to FGMCC. For some reason after I pulled up the PDF then highlighted the URL in the browser window I could not "paste" it to the response area on this thread. Didn't just wanna fool with it so I just gave you guys the text for the inquiry. Patience is another thing that fades along with stamina as we get older. Some who have known me for years and years would say I was never patient and that might be so but one thing is sure I am not getting more patient as the days pass! LOL No worries, it all works out in the end. I have plenty of time, so I don't mind looking for things, posting them, etc. The link issue is a bit funny sometimes, even this time I had to go about it a couple different ways to display what's above. I tend to do most of the stuff here on a PC as well, as opposed to a lot that may use a cell phone. For me, it's just easier. 1 Quote Link to comment Share on other sites More sharing options...
Alex & Keith 72 Monte Posted November 12, 2022 Author Share Posted November 12, 2022 Ray - sounds good on coffee. Will be leaving for Florida and gone until Christmas. Monte should be on the road early year and coffee awaits! Keith. Oh so close…after three years 2 Quote Link to comment Share on other sites More sharing options...
willie Posted November 12, 2022 Share Posted November 12, 2022 Looks Great, K & A, I like it!!! Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted November 12, 2022 Share Posted November 12, 2022 2 hours ago, Alex & Keith 72 Monte said: Ray - sounds good on coffee. Will be leaving for Florida and gone until Christmas. Monte should be on the road early year and coffee awaits! Keith. Oh so close…after three years Ok on the coffee when you get back to "The Atl". Have fun in Fla, enjoy Thanksgiving. Will get in touch as we get near Christmas. Looks very nice, greatworkmanship. I am looking at all the room you have around that engine! Wish I had some of that but the BBC and A/C sure eat up a lot of space when it comes time to do some work under the hood. In the summer I am so glad I converted it to factory A/C but things get a little close with all that A/C equipment. Quote Link to comment Share on other sites More sharing options...
Alex & Keith 72 Monte Posted December 19, 2022 Author Share Posted December 19, 2022 Ray, Joe or others, I’m having trouble finding led lights for the two Courtsey lights under the dash by the lower side vents. Bulb is marked 97 and is a bit larger and squat. Looked on line and a couple auto stores no luck. Any guidance? AlsoI have a positive wire running to the drivers side under the hood by the firewall. This is run off the inner ignition post on the fuse box and also runs to the starter. What else would have power off of the ignition? Car is not all OEM wired so it may be non typical. Thanks in advance for all your experience and expertise! Keith Quote Link to comment Share on other sites More sharing options...
stangeba Posted December 20, 2022 Share Posted December 20, 2022 I was lucky, in July 1985, I bought a 71 with the 350 and no A/C just like mine and swapped everything including all the harnesses under the hood, and it worked great! Then I went to sell the doner and the starter went out so I had to drop the price. I wish I could remember what that price was. Good luck! Quote Link to comment Share on other sites More sharing options...
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