finished product
So here's my first completed project. Underneath all the felt is a Speak & Math . The original buttons are all operational. As I'm sure that there's no mystery surrounding what a bent Speak device should sound like, so I'll not post a clip. That being said, my excitement compells me to tell you about the mods.
The switches are two different loops and an angry switch. The big square button is a momentary loop that can occasionally produce distortion when used in conjunction with one of the other loops. The top small button is a tone, and the other one makes a fluttery sound. There's also some body contacts on the sides.
I'll cop to using a schematic for the pitch knob (as I had pretty much no idea at all how to do it) but the rest of the bends are the result of trial and error. Anyway, here are the front and back views: