63-66 a body ac options
There are two issues. The cabin unit is early A specific. I will use a knee-knocker in my 2 A's. If tempted to use a factory climate box, know that factory AC cars had a different firewall, so a lot of work to adapt to that.
The compressor is engine-specific, other than the fact that early A's have a slightly narrower engine bay. Several bracket setups for V-8 (see Bouchillon Performance, Vintage Air). For slants, you can find a post that details all the options. One option is finding ~1978 Volare/Aspen Sanden brackets, but may want to use a narrower battery (some newish cars use) so the bracket doesn't threaten punching a hole thru the case.