I was worried it might come to that! I'm grateful to the Moped Gods for a few things, though:
1. The Puch's magneto and engine are one unit so there's no ignition wiring to worry about.
2. There's only three "mystery" wires.
3. Mopeds don't have things like CD Players, GPS systems, and clocks along with the complicated wiring that goes with them.
My guess for the three remaining wires are: ground, +6V, and engine kill.
Can anyone tell me if I'm way off in my assumption?
I'll get the ol' voltmeter out and try to figure out what does what in the next few days.
Thanks for your help, Ree!