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Jag-Stang Mods
The start of all my guitar mods was me happening upon a tiny circuit called "bazz fuss." It's like five components. I thought, "surely I can fit this into my guitar without any issues."
In the course of this project, I customized the fuzz, had to carve out space for the battery and another circuit, and really got to understand the guitar's wiring.
(click an image to uncrop and embiggen)
Shielding. Copper in the body, aluminum on the pickguard. 
Pickguard in place with added kill switch. 
Close-up of new tone circuit. Normal to cut treble, pull to cut bass. 
Everything back together. New knobs with better grip on the sides to make pull-switches easier to use. 
My secret weapon (don't tell). It's a mercury tilt switch from an old thermostat. Tilting the guitar up adds a Dan Armstrong Green Ringer (octave fuzz which sometimes sounds like a Ring Modulator) to the circuit. It's a little like Guitar Hero Star Power. 
New wiring and sketch. There was supposed to be a tremolo circuit in there, but I yanked it because I couldn't stop it from clicking. I later learned that it's a common problem with tremolo circuits and I figured it out by the time I got to modding my Ric. 
This clever little doodad is a thumbscrew so I can adjust the tension on my whammy bar on the fly. The default method is using a hex key and is just terrible.
