[GMC Jim]

Personally, I feel that installing the original factory air conditioning parts is the way to go....One can save bunches of money compared to aftermarket units and besides the installation will be stock....Also, there are many GM autos of the 68-72 vintage that use the same parts as our trucks.... When I bought my truck ( about 12 years ago) the compressor, condensor were missing. The condensor inlet/outlet had been sawed off. I replaced all the above mentioned missing parts from a 1971 Pontiac Catalina Station wagon, including the hoses. Purchased a new receiver/dryer and installed along with the hoses from the Pontiac. My system has been working fine since installation... The condensor and compressor were of larger size than the stock GM unit. No problem fitting the units and the larger capacity condensor contributed to the effeciency of the system; I believe. If you decide to use previosly installed parts , I definetly feel that the unit should be obtained from a vehicle that has the parts, hoses intact, as this will ensure that no foreign material has entered any part of the system.. Also you might want to check with an air condioning facility as to cost of the evacuation and re-charge with Freon 12.. .. At the time I did mine, Freon was only about a $1.25 a can ( took 4 cans as I recall!)...