This switch is for converting to the GM one wire. The red wire connects back to the main red battery terminal on the back of the alternator and the white wire connects to your ammeter. Fits:
The pieces are well made and fit well. That said, I was a bit disappointed that the metal wasn't straighter. I'm doing a show truck and had to do some work to make them look well. I'm Very happy to have found the scarce parts, thank you.
Trying to re-hang the rear leaf spring with an add-a-leaf helper on my 67 commando wouldn't have been possible without the extra length on these u-bolts.