I've just come across this layout, and it may be just what the Fuzz Doctor ordered. The Catalinbread Manx Loaghtan - a Big Muff (Rams Head?), but with a Baxandall tone circuit. The sustain control also has a much wider range.
I'll be building this one for sure!
By the way, D1-D4 are 1N4148, and D5 is 1N4001.