I built it as per Chuck's schematic. Except I used a 10µF cap at C4, BAT46 diodes, a B100K pot for Gain and 2N5088 transistors. Otherwise absolutely identical.
I quite like this one. Gnarly slightly sludgey overdrive with a hint of fuzz.
I'm going to have to try that one out... I've been clearing out breadboards as I have about 3 circuits I want to test out... including my next "semi-original" project...