Following this post (http://www.madbeanpedals.com/forum/index.php?topic=15298.0) I thought of a good mod: the "Squish" switch. Moving the bias point of the collector of Q2 down (well, technically up since it is a negative voltage) from -4.5v to somewhere between -2.5 to -3.5 v has the effect of "squishing" the fuzz a bit. It gets you a little more into the Eric Johnson fuzz range and is actually quite pleasant to play. Here's how it would work:
Socket R3 and jumper it. Dial the Bias trimpot until you get into the -2.5 to -3.5v range on the test point. Use your ear to find the right "squish" amount. Once you find that start trying different value resistors in R3 to get the test point reading -4.5v. It will probably be somewhere between 1k and 4k7, but YMMV. Leave the resistor in, and wire an SPST (or SPDT) switch to either end of the R3 socket legs on the bottom of the PCB. When the switch is off it gives you the normal bias. When the switch is engaged, it shorts R3 and goes into "Squish" mode.
If anyone feels like trying this, let me know how it turns out.
Sounds cool... Might try it?!!