I saw this one on JohnK's page and decided I wanted one, so I went forum-diving for a schematic and put this layout together. Haven't built it yet but I checked it over twice and it looks good, so should be fine. Sounds like a really awesome bass fuzz, I'm sure it's usable on guitar too. It has an interesting topology that is admittedly refreshing after seeing so many rehashes. It's probably an adaptation of something I'm not aware of
I've incorporated a few simple mods to improve the functionality of the Blend control as described in the FSB thread (namely the 390K resistor and the 47uF booster cap on Q3. Original mod was 100uF but chirping at high gain was reported, so try values as big as you can go without noise).
If anyone goes to look at the schematic, please note that the transistors are not
labelled consistently with the schematic. Q1 and Q2 are the same, but then Q3=Q6, Q4=Q3, Q5=Q4 and Q6=Q5 (layout=schematic). I've also omitted the filter cap from the board but it was only 22u and I suppose you could just add it to the jack. I think it was actually done this way in the original.
EDIT Just cross-referenced the 2N3707 and apparently NTE199 is the equivalent, for those whom obtaining NTE parts is easier. The 3707 are actually quite expensive on eBay.
I stand watching the steam-liners roll by...