Well, I started putting the wiring back in the bike last night. I started at the rear. The tail light is original issue so the parts are very old. The guys who restored it simply spliced the original wires into the harness for the 12 volt upgrade. I wanted to improve on this so I ended up soldering the new wires I added to the components. What I learned from that is that I need a new soldering gun!

The tail light upgrade actually went better than I anticipated. The brake lever switch is another story.

Getting the wires in the proper position was a chore. I wrapped the wires in a protective heat shrink wrapper and ran them through the body of the bike to the brake switch. That part was easy. However, I am using 16 gauge wire so it is a little larger than the original wiring. This made it somewhat of a tight fit up where the switch attaches to the frame. After fighting with that for some time, I got it all attached.

This is where I show my ignorance. How does this work? According to the wiring diagram, the wires for the brake switch junctions with the wires for the brake light AND the power source. I can't see how that would cause the switch to activate the brake light. It seems the switch would need to be between the source and the bulb.

I am confused.