Hi Vaughn, i was running into the same situation with my 7T1.
here is what i found out,, you want to see about an inch and a half out the bottom. But not flush and not as far out as the complete bumper. This came from Cameron a reliable source out of Burnaby BC that restores,Montes,chevelles etc. I to searched and could not find a real data on this.
hope this helps,
c you in Penticton
Bill