The first problem I can think of is that all the pots and faders are likely to be logarythm taper and not linear taper. Log taper is used for audio volume controls, linear taper for MIDIbox controls. Still, at the very least the case, front panel, knobs (ie the actual knobs and not the pots), and maybe the power supply would be useful. If you were into heavy desoldering sessions you might be able to reuse some other loose components like LEDs, but it's a lot of work.