find the 2N5809 that goes to the output
replace 100k from 2n5809 base to ground with 47k
replace 2k7 from 2n5809 emmitter to ground with 1k
remove the wire from board out to on/off stomp (”on/off 1”)
run a wire from board out to volume pot (100k) lug 3
wire lug 1 to ground
wire lug 2 to a 1k resistor
wire the other end of the 1k resistor to on/off stomp (where board out used to go)
Same as method 1, except:
replace the 2k7 to ground with a 100 ohm (instead of a 1k)
replace the 4k7 from the collector to V+ with a 2k7
you still need to replace the 100k with a 47k and do all the wiring the same.