I saw a layout at tagboard effects and made a schematic from it in falstads circuit sim.
Changes I made
1) 10k resistor following the first stage to pad the second stage from clipping. I like to run my Vol full tilt but I dont want my active/passive switch to make that big of a jump. This can also be acheived my adding a 1k resistor inline to the cathode bypass cap of the first stage.
2) Anode bypass cap pof the second stage to pad high frequencies above about 5Khz. Eliminates hiss for hot pickups.
3) I didn’t have zeners so I just omitted them.
If you are going to make this a pedal you will need to add extra power filtereing. My tests showed excessive noise with a OneSpot inside of a sheilded enclosure. 100Uf on the +- power inputs may do the trick. I am running it onboard on a 9v battery with very little noise.