I was searching for wiring schematics for bass guitars that have 2T2V and a switch....and just stumbled onto this.

http://www.ak-line.com/medium/Bassschaltungen.pdf

This is written in German, but the schematics are pretty clear even if you don't. If something is not clear, I read German fairly well, so please feel free to ask me.

The title of the work is Cadfael's (no longer so) Small Collection of Circuit Diagrams: Passive Circuits for Electric Bass (and a few Active Circuits).

He has collected literally hundreds of bass circuit diagrams.

If you remember that "Potis" is "pot" and "Kondensor" is "cap" and "Masse" is "ground or earth" you can get through most of it.

I am just blown away that someone did this for bass!