don't use a one-wire alternator, unless you don't mind the fact that your alternator (gen) light will no longer function.
buy a alternator for a 1989 Olds Cutlass Cierra with a 3.3L v6 or a 1986 Astro Van with the 4.3L v6 with the 110A alt. both will fit.
pick up the matching pigtail, available at most parts stores.
find the brown wire that goes to the regulator at the front of the car, cut it off right at the regulator, re-route it over to the alternator.. attach it to the pig tail, pigtail should only have two wires in it.. if its' 3.. I can't remember which wire it is (I'm not at home)
the LARGE red wire in the pig tail gets connected to stud on the back with the big wire and you are done.
I have this set up on my monte and it's FANTASTIC.. the CS-130 series alts charge WAY better at lower rpm's then the SI series.
(both those applications I listed above are CS-130's)
the CS-130 is slightly smaller then the alternators the monte's came with, but if you just lean down on the alternator bracket it will fit ok.
this is a pic of my engine with the CS-130 alt (with a custom alternator fan installed)
http://home.comcast.net/~kc8oye/Engine/DSC02407.JPG