Help with My Incomplete A/C System Please!

[Davidf]

If it was me, I would do the following:
1. Salvage the condenser, hard pipes, and receiver/drier mounting clamps from the donor.
2. Purchase new hose assemblies.
3. Forget about any salvaged A6 compressor...it will probably be worn out and rebuilding it will probably just end in a leaky front seal. Instead, purchase a new Pro6Ten compressor...a direct bolt in replacement and lighter. Get the compressor mounting brackets from the donor.
4. Get alternator brackets to move alternator to other side of engine. Or, get compressor brackets for left side mounting and have custom a/c hoses made. Many GM cars/trucks had a/c compressor mounted on left side of engine.
5. New receiver/drier.
6. New expansion valve
7. Check POA valve and (check) calibrate for R12 at 29.5 psi.
8. New heater water valve...normally open (i.e. vacuum closes valve).
9. Remove evaporator and have a/c shop pressure check with nitrogen. Pressure check the condenser as well. Have them reverse flush both. Ensure POA does not have trash in it from being left open.

Hope this helps. Also, the above assumes you are staying with R12. If you convert to R134a, you will need larger condenser, calibrate POA to 26 psi (I think that is correct, look it up) and then definitely replace the compressor as the higher head pressure will surely cause the front seal to leak on an old A6 compressor even with new seal. But, in LA with the mild summer temperatures, you might get away with using R134a with the original condenser meant for R12. Good luck.