One of the other weak points in the AC is the hoses and trie ends. It seems the system was a modular one with some sort of quick disconnects. I had to have mine replaced and the shop had to custom make the hoses and weld them to the old ends to allow for reattachment to the compressor and evap/condensor.
The AC unit is a hybrid of GM parts and what looks like an aftermarket unit. You may need to consult an AC guru to figure out where the wires go. It could be something as simple as a loose wire.
WBCCI #5501 AIR # 49
1978 Argosy 28 foot Motorhome
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