1967 Camaro RS wiring

I need help with the wiring on the headlight doors of a 1967 Camaro RS. Previous owner of the car painted the engine compartment and unfortunately all the wiring. In trying to wire up the limit switches on the headlight doors, I have run into a problem trying to determine which wires go where. I think I have a light colored wire (possible white or yellow), a purple, and possibly a black. Can anyone tell me which wires go to which end of the switch. On each switch there is a wire coming off one end that goes to what appears to be a ground on the switch itself. Can I assume that this is the ground side on all four? I'm enclosing some photos which show the switches and the ground wire coming off the wire. Any help would be greatly appreciated.

Peel back the coating on the harness till you can see the factory colors,or use some laquer thinner and gently wipe the black paint away.
The other method is use a fluke meter to find out which wire is which.