By 1965, factory AC cars had a different firewall. I understand it varied on the passenger side, around where the blower motor protrudes. If you compare w/ Google Images, you should verify that was a non-factory AC car. In 1965, factory AC was so expensive that it was a fairly rare option. There were many after-market systems (Western Auto, K-mart, Sears, ...), especially as systems became cheaper in the late 1960's. I think rear AC was an option in full-size cars then (Imperial, New Yorker), but am sure those also had dash evaporators.
Re other parts to grab, that manual gear-box and mating steering column are desired, since people using headers (w/ V-8) often can't fit power steering. The rod-style throttle, carburetor, and kick-down linkage is rare and thus valuable. The PCV "stove-pipe" is rare and an easy pick. It was also used on V-8 engines then (at least my 65 Newport). A part near the driver's shock absorber top looks interesting (rare?). The 1965 bulkhead connector (indeed entire dash wiring harness) is desire-able since better power feed-thrus. I put one in my 1964 car (but won't work for 1966+). If the headliner steel bows and clips are still there, grab them, and number them as you remove. GT was a trim level, so if not dented, it can be re-polished and probably fit to a lesser car. If the front trim is there, it is valuable, though usually dented since aluminum. Everyone is looking for good front "candy-cane" trim for a 1965.
You know that everyone not in SoCal/AZ is amazed at that rust-free body. You LA guys see that all the time in junkyards, you lucky sods.
