And then, I ran into a problem with the wiring. I had calculated that I had _just_ enough pins in the Pi to connect everything, but that assumed that the Pi had analog input pins. Which it doesn't. The analog inputs are needed to read the potentiometers. I could add ADCs, but even that would increase the pin count. So, plan B: I'm using an Arduino to read the inputs, and send the input events to the Pi via a serial connection. This has the added bonus of less wires running from one half of the case to the other. Now, if some idiot just hadn't installed the Arduino to the space that was already taken up by the power switch... Oh well. I'll see if I can somehow jam them both in there.