Couldn't resist to draw a schematic and a layout for this interesting mutant of a circuit that just got traced.
First two gain stages is almost identical to a Jumbo Tonebender (except for one cap and one resistor value), the third gain stage is almost identical to the saturation stage in a Tonebender Mk. 3. Transistor bias is quite different with the zener diode, though. Tonestack is Big Muff style followed by a Volume control.
Note that earlier versions had 100nF or 470nF instead of 10nF so it might be worth socketing that cap.
