Single speed wiper switch decoding

Okay. This took entirely too long to figure out but here it is. The part number shows that it's a switch for a '65 Imperial or Coronet. That's odd because those cars should have come with a better wiper setup. Indeed the service manual wiring diagrams for those cars only show 2-speed, 3-speed, or variable wipers. Must be nice.

My guess is that the switch I have is a one-size-fits all factory switch that superceded other switches as time passed, or maybe it was generally used for all 1-speed and 2-speed setups. But I'm always willing to be wrong.

So only three wires are connected:

1. The black wire w/trace goes to pin #A, and then off to the two pin motor connector.
2. The dark blue wire goes to pin #P1 (the double post seen above) and then off to the motor connector.
3. Pin #B goes to 12v battery switched positive at the ignition switch. There's no relay involved which is a surprise given the amount of amperage the motor pulls. The wiring diagrams say is supposed to be BLACK wire but mine is RED.

For my application I'll connect Pin #B to a relay with a fuse and find a heavy +12v connection.

Sadly, none of these pins activates a washer fluid pump and the Pin #W terminal that's supposed to do the job isn't connected to anything at all. By that I mean that the switch has a push button for the pump but there's no Pin #W to activate one. Weird.