Next Distortion X

Got one of these in for repairs. CMOS inverter overdrive made in the early 80's.
Seems somewhat rare, can't find any schematics or such. So I traced it out.

Some values are missing but I'm fairly sure it's correct. Interesting circuit design.
That weird 5-terminal potentiometer is crazy
worn down, good luck finding a replacement..

Kitty cameo
Distortion X

Distortion X PCB top

Distortion X PCB bottom
Distortion X schematic