Another source for original 6 volt wiring is YnZ.
https://www.ynzyesterdaysparts.com/
They can modify their looms if needed to your specs.
If you plan on converting to 12 volts I used a Rebel Kit to rewire my '39 p/u when I converted it to 12 volts. Easy install. I've been told they have great tech support but I didn't need to use it.
Hope you have better luck with CPP than I did with a defective brake light switch.