1965 Barracuda Heater/ A/C

My car seems to have never, well maybe, had a heater, there is a plate over the fan cutout in the engine bay, there is a plate over the heater controls area, and there are no internal parts behind the dash. The question is, is there a aftermarket Heater / A/C unit that will fit, with a reasonable about of work? I would also like to put dash air vents, floor vents, and maybe replace the defroster vents with some that wrap around the windshield like a more modern car. I have 2 extra dashes out of junked 1965 Barracudas for mock up.

Thanks
Gary
1965 Barracuda
1965 Barracuda Hulk
1965 Barracuda Rust bucket,
and 1965 Factory V8 four speed, minus engine and transmission, and a mess