I have a 71 Chevy truck with factory AC that hasnt worked in years. It's all there but the hoses are bad and the compressor is locked up. I dont care to rip it all out and install vintage air because I want to keep the factory controls and vents. Old Air Products has an upgrade kit that does away with the POA valve, mounts the drier on the evaporator like a later model, and uses a low pressure switch. Is it possible to mod my existing evaporator with parts from say, Napa instead of buying their kit? How would you wire that up? Heres the link to their kit.http://www.oldairproducts.com/catal...Make=Chevrolet&Model=PickupC2FK1030&Year=1971 I'd love to know what that evaporator originally fit.