It's a cool idea to put a fuzz inside a guitar!
Thanks guys for suggesting the Eagle Claw. :)
I've found that it works best with hot pickups, so it wouldn't be my first choice in a strat. But if you would want to try the Eagle Claw I can draw up an even smaller PCB layout for you, upload the design to OSH Park and share the project. That way you can order it yourself directly from the fabricator. A small layout like that is just around 10$ with free shipping for 3 pcs.
I actually bought a cheap guitar just for the purpose of putting a fuzz inside it. I didn't want to ruin a good guitar... It's a Harley Benton jazzmaster style guitar, but it's actually more than decent. Better than alot of Epiphone and Squire guitars that I have played. I never got around to putting a fuzz inside it though because I could never decide which one to choose. :P
check out my building blog at www.parasitstudio.se