A/C question...

Ok, I can tell you the firewall is different for sure as I have already done this change. Unlike the E-bodies this is a very simple switch. All you need to do is take a template of your a/c fireway and transfere it to you non-a/c and make the cuts. I think we had to drill a few extra holes for the heater box too.

So make the blower motor hole a bit bigger, drill an extra hole or two for the heater box studs and you're pretty much set.

The E-body on the other hand has the blower motor section stamped differently and has a quarter inch raised flange all the way round. It still can be done but is much harder to make look like factory.

Good luck....