Sorry to dig up an old one, but I figured I would contribute seeing how I've got so much from FSB over the years.
I have a Bass Fat Drive that I bought a while back, and was planning to sell it but I figured I'd trace it out first:
I measured all the caps and compared the resistor values to the schematic PedalPCB posted. The only differences that I could see is four caps, which look like the footprints were added to the PCB in addition to the guitar version caps.
C3B: 15n
C4B: 150n
C6B: 150n
C8B: 56n
Everything else, including the pots, diodes, IC's, etc look the same as the guitar version, with the exception of R9, which I think for both versions is 16k.