Triumph Repair: Spitfire windshield wiper motor circuit, windshield wiper motor, column switch

Question
I am restoring a 1973 Spitfire. The previous owner replaced most of the wiring with a Painless Performance 30001 12 circuit fuse center. The problem is how to connect the wiper and switch. If I knew what the terminals on the plastic box on the rear of the wiper motor should be connected to I could figure it out. The various manuals do not identify the functions of these terminals.

Answer
Hi Bill,
I could not find a diagram of the inside of the wiper motor either. However, One time in one of the dealerships I worked in I had the same problem where a customer wanted to wire up a Lucas wiper motor to operate by toggle switches so we just opened the wiper plug up and made note of what wire did what.
The two speed Lucas wiper uses three wires on the motor. By looking at the internal wiring of the plug on the wiper you will see that the three motor wires are negative and two optional power wires. A 12v battery and a couple of test leads will allow you to ID what wire does what on the motor. Then look at the park switch. As I remember the parking of the motor disconnects the power supply and grounds the motor wire so as to be a electric brake to stop the motor from coasting when shut off. I don't remember what color wire does what but I do remember how it operated.
Just keep in mind that the two optional power supplies changed the speed of the motor and when switched off the motor becomes a spinning generator so the motor wires are disconnected and grounded to act like a brake. The park switch does the disconnect when the column switch is switched off and when the park switch disconnets the motor. It is grounded so the motor (now a generator) will brake and stop quickly.
Sorry I couldn't be more specific but that comes from my momory of 35 years ago.
Howard