Thanks Sixto The fact that both my manifold pressure switches were of the normally open variety prompted me to go back over everything I had done before. I pulled the switchover off the car again and retested it with my trusty mitivac. The valve is shaped like a silo with a vent covered with a plastic cap on the top, with two air connections coming from the bottom. As you look at this unit from the front of the car the air connections are side by side. I plugged the one on the right side(R)and applied vacuum to the one on the left(L). Without 12 volts applied I pumped about 16 in hg and found that the vacuum would leak down very slowly. Pumped vac back to about 16 in hg and applied 12volts. The vacuum dropped immediately to about 6in hg and held there for an extended period while 12 volts were applied. It seemed to me that this was likely what the unit is supposed to do.I put the unit back on the car and connected the ALDA line to connection (L) and the manifold line to (R). Test drive shows no loss of power so perhaps all is well. Further review of the wiring diagram shows that the active terminal of the manifold switch is also connected to terminal 1 of the OL protection Module. I expect this would enable the means to protect the transmission from over pressure . (Trans pressure switch on terminal 5 of OL protection module.)-- Connection of the manifold switch to pin 1 of the OLM would eliminate the possibility of using a normally closed switch.
Went back to the notes I had made on the original test on the switchover and made no sense of them. Sorry about the confusion. Moral of the story-do your work when its warm and take your time.
Does anyone know if the 82 transmission has a pressure switch for transmission protection? I noted an unconnected wire hanging down.