I would say we are beating a dead horse at this point however in the spirit of accuracy and correct information, please show me where the bodies are different, but for the holes in the firewall. Here is a picture of the firewall pad, non ac top vs ac bottom.

I can't speak from experience with the AC differences in a 68-72 A-body shell. But I know from experience that on both 61-64 Impalas and on 64-67 A-bodies, (A) the firewall / toe-board section is different, (B) the part of the firewall above the seam is different, (C) the right inside kick panel / cowl section is different, and has the big "vent" hole farther up and a completely different shape, and (D) the part of the right kick panel / cowl section outside the car (behind the fender), is a completely different shape (not just the holes, but also a larger stamping that goes farther straight down towards the ground before it bends back towards the rocker)

Actually, (C) and (D) are a single piece of sheetmetal, but part is inside the car and part is outside, and you cannot change the entire piece in a single unit at one time without cutting the entire right side of the cowl off the car.

So you can easily slice new holes in the firewall for AC; but to alter the right side of the cowl for AC you have to add metal at the lower part of the interior vent hole, reshape the upper part of the hole, and "build" an additional box area at the lower part of the outside of the right corner of the cowl. Can it be done? Yes, as I have done it to a 63 Impala and a 67 Chevelle. Is it any fun? Heck no. Can it be done without taking the front fender off? I seriously doubt it, and sure wouldn't want to try!

Again, no idea about 68-72, but I would think the complexity of the AC cowl differences was at least as involved as on a 67.

I know this is off topic from the original post and sorry for hijacking.
The non AC cars bodies have Upper Air Outlets. The AC bodies do not have these. Totally different. As Jeff states, it can be done....yes but it would be a PITA to do it correctly.

Just a comment regarding AACA Grand National judging criteria. The cars are judged based on the options that were available from the factory and/or dealer as new cars. For seldom seen rare options, participants may be asked to show verification that optional equipment was available. I had to do that for the liquid tire chain option on my 69 Camaro. The validity of option combinations (such as with this car)is more difficult for judges to question. Grand National events included cars built from from pre 1900 to 1998. So, getting this far into the weeds for every car in every generation would be impossible. Heck - it’s sometimes difficult to get agreement from the experts on this forum regarding a very narrow window of cars.

AACA Grand National shows are pretty special if you’re a car enthusiast. Even regional shows like AACA Gettysburg this past weekend bring out some incredible cars. There was a MB gullwing sitting across from my car that the owner drove (not trailered) 200+ miles to the event on Saturday. Overall, great cars & great people IMO.

MB gullwing

How do local AACA clubs compare to something national? Local car shows I have been to rarely do anything more than a mirror on a stick walk by the 2 sides, glance to make sure it has an engine, interior and sometimes doesn't bother with the trunk.. Largest in my area I have been to more than a couple times avg around 500 cars. I never expect anything as far as an award/trophy or a pat on the ass. It's more for the enjoyment to get outside but some guys think that is how judging is supposed to be done. But maybe I am only seeing localized issues. In fairness, I have only gone to 4 car shows in the last 8 years but the AACA local chapter is always the ones doing the judging. Maybe the reason is they are not judging those events like they would their own but they are recognized on the flyers of said events.

ive seen another w-31 that has a/c supposedly "added by owner".
it was actually at MCACN but the hood was shut.

Those of you who missed out on it have another chance.

https://www.ebay.com/itm/36427080866...mis&media=COPY

Lmao

lol