Want to add a/c to 66 Barracuda as long as the car is apart.

you could go this route and get a aftermarket Sanden compressor and custom hoses made locally to your condenser (look for a good parallel flow unit) you won't find that in most kits. hhere is a slimline that should work.
Slim Line Under Dash A/C Evaporator - Heat/Cool/Defrost

or the kit with a larger inside unit
Complete Under Dash A/C Systems
I'd look around for a kit that you can mix and match to get what you need.