I saw a layout at tagboard effects and made a schematic from it in falstads circuit sim.
These amps are cheap and with a few mods they sound fantastic. I started with the mods on valvesphere and then graduated my own to make it less flabby in the distortion. Check out the rest here.
The Angry Bear is basically a modified Big Muff, Pharaoh Fuzz style with a boost and lots of clipping options.
This pedal I made with a PCB ordered from General Guitar Gadgets.