Lake Butler MIDI Mitigator RFC-1
Billy uses a "Lake Butler MIDI Mitigator" for his MIDI switchboard. Most of his MIDI controls are set up to go ahead in the song and make changes automatically according to time, or a certain note he may play that will tell his rack effects to use what settings and how. But, on the switchboard, he has one button for almost every sound he could use live.
[product info at Synthony's Synth & MIDI museum]