I have a question for you. Do you have a high/low pressure switch on your factory AC?
Mine was converted for the modern Freon and a high/low pressure switch was added to the receiver drier canister but it wasn't wired up to the compressor and I'm trying to figure out if it should be and if so, how?
My instincts are to just splice it in-line to the compressor power but I'm not completely sure that's right.