What is involved in switching to "dumb" A/C from ATC?
 

I have a 68 Bonneville with ATC, but when I got the car the compressor, condenser, dryer, brackets, etc, were all missing from under the hood. As to the ATC stuff on the inside, I believe most of it is inop if for no other reason than rotted vacuum lines and rusted diaphragms and levers.

My question is how hard is it to convert to the regular manually controlled AC?

I have at least some of the under brackets from a parted 68 big car, but nothing from the interior. I think the evaporator is still in the case on the firewall.

Is the best bet to find a manually controlled A/C from a parts car and swap the box on the firewall and all controls? Is there any way to make the ATC stuff work to supply even just a cold air to say the outets on the dash?

Just forget the entire factory parts route and just buy an aftermarket kit? Any recommendations as to the best kit?