Based on this schematic by Jack Orman and the layout by Carsten Bocker.
There seems to be an error in the layout, although I remember building one that worked?!? Anyway: give me a few days to sort it out and I'll get back on this!
Use 2.2M for R1 and R2 for higher input impedance (General Guitar Gadgets).
Bill of materials
|2 jumper wires|
|5 trace cuts|
Click here to see the bill-of-materials as a list or download it as a comma separated values file (.csv).