Jon has contributed a lot to the DIY pedal building community and I always learn something new when I layout one of his circuits. So I think we'll have a Jon Patton week, starting with the Clipper Ship. There's a good bit of flexibility with this one. Q1 can be pretty much any low gain transistor, germanium or silicon. If you're using a germanium transistor, use a germanium diode for D2 (if you're using a silicon transistor, omit D2). For D3-4 use anything with a low clipping threshold–1N60, 1N34, BAT41, etc. Q2-3 form a cascaded JFET stage (much like the AMZ Mini-Booster and a ton of other designs). Way more info on the circuit can be found here, including the schematic. I've laid it out for a typical 1590B with board mounted pots. Oh, and D1 is a 1N5817 or similar for power protection.