1950 Mercury truck

I'm helping my neighbor to a complete frame off rebuild of his Mercury truck back to original condition and I'm wondering if anyone has a pdf image of the wiring diagram.
The truck was in pieces and disassembled completely when purchased.
To be specific the heater motor wiring and switch assembly.
He has two motors both are 6 volt 1 has 4 wires and the other has 2 wires.
I've done a restoration of my 1950 Chevrolet 1 Ton and could find tons of information but when it comes to his Mercury not so much!!!!
Any help with information would be appreciated.
Thanks
Doyle

 

I would think it's gotta be the same as a '50 Ford, but that's just a guess

 

Thanks