Details of this project can be found here – as I started with a modded Pete Cornish SS-2 using the Joe Davvisson diode-compression op-amp, and then moved on to this.  Essentially the same as the SS-2, but with the addition of a lo-cut.  

After a bit of testing, I’d suggest a C50k for the sustain pot, followed by B50k, and A50k if you have none of the previous.

CORNISH SS-3 WITH DIODE-COMPRESSION OP-AMP – VERO LAYOUT

The layouts works – I added a buffer on top of this build.