Moving on to the shift console of my '81and I have one more terminal that doesn't have a mating connection. It's just forward of the front console bracket and secured to the tranny tunnel. There are 5 wires: Blue, Black/White, Brown, Purple/Black and white. I've been back and forth through my service manual and assembly manual. I see no reference to it. Can anyone help me out here?

Power windows switch...???  🤔  Just a guess.

The purple wire in the connector usually indicates it is related to the starting circuit. Neutral safety, anti theft, etc. Purple is also used in HVAC systems, but not typically inside the cabin area. I have scrutinized the '81 wiring diagram, and see NO 5 wire connector inside the cabin that contains those wire colors. It is possible it is for some optional equipment(rear defog, etc) that perhaps your car does not have. 

btw..do you happen to know if this is a St. Louis built car, or Bowling Green?

For my 1981 St. Louis blt. car, this is the vehicle OBD1 diagnostic connection.

See photo of the 81 wiring diagram of the Diagnostic Check connector.

Since this is early OBD1 a 5 pin led for checking codes is probably not available.

There maybe another 1 wire )tan/blk stripe wire connector floating in there as well. It is for the cars with an  automatic trans.

Hope you can read the lettering.

Thanks JPD. I did see a reference to a diagnostic check in the service manual and thought that this might be for that.