Korg DW8000, Mono/Poly, MS-20...

I've just bought a DW-8000 with an Angel City Turbo board, and while
I'm looking forward to getting to use it, there seem to be a few
shortcomings (in particular, it doesn't look like Voice A and Voice B
have separate LFOs.) These may simply be due to the limitations of ROM
size and/or a 2MHz CPU, but since I enjoy small-systems hacking
anyway, I figure it couldn't hurt to take a look under the hood and
see if it couldn't be tweaked a little further. I don't suppose the
original source code is available, or at least a commented
disassembly?