The gains of the transistors matters.
''8k2'' doesn't adjust.
Q2C resistor should be adjusted so the circuit bias is 'correct' [by ear.
5k6 through 15k6 is a good range for most Si transistors, and doesn't tend to gate-out at either end of the trimpot or knob rotation.
A 5k6 > 10k pot in place of ''8k2''.
Could be 20k trimpot or panel pot.
Makes it possible to sweep the DC bias and try settings by ear, or by adjusting to various idle-voltages on Q2C and trying possible bias's out for a while.
Another thing to do when choosing transistors and such is to use the guitar volume if you want to find the 'cleans up at guitar volume' = gain adjustment.