A big thanks for the tech help ..But.

Did you see the picture of a homemade a/c built on a styofoam ice chest ?
Yeah it was cheezy looking but doesn't have to be. I see vintage metal clad ice chests at the flea market often. Something like a BMW rear defrost blower could mount under the lid too. Sit it up in the back seat, poke it drain and power connector out where a seat belt would, add ice. Will the ice cost more than the fuel millage difference of conventional a/c ? Who knows.
I do think that proper cabin insulation, a little window tinting and this homemade alternative would make the long rides a heck of a lot more tolerable if not totally comfortable.
For the short drives a couple of frozen jugs could be your companions. The jugs would need corrugated sides to be more efficient. Have I put too much thought into this ? LOL