Vintage Synth Repair

I recently picked up this baby at a local Salvation Army for 15 bucks! The thing is in terrible shape with a missing cheek but that didn't stop me at the time. I got it home, dusted it off, and plugged it in.

Alas, to my disdain the bass section works perfectly fine, but the treble section does not. Nothing makes a sound, not on any position of the drawbars, even. So now I have a 58 pound, 24 key monophonic bass synth. Which is cool, I guess, but I'd REALLY like this entire thing to work.

I've repaired a number of synths but when I opened this up, my jaw dropped. I've never seen so many PCBs aside from a modular in my entire life! I was wondering if any of you could point me in the proper direction as to where I should be checking, because if I have to test everything on these boards I'd die before it is repaired.

Thanks in advance!