The Tres Hombres is a distortion/fuzz designed by Marcelo Trípodi on the DIYStompboxes forum. In a nut shell, it's three similar germanium transistor stages with fuzz and volume controls. There's also a switch to add an extra capacitor at the input to fatten up the sound. Marcelo recommends 2SA101 transistors with an hFE of 50 and leakage of 150ua. Socket and experiment. The perf side of the layout below is for positive ground, and the PCB is for negative ground.