(from what I recall apparently happened) Geoffrey Teese sent Stewart a kit (Teese used to sell drop in RMC3 kits), then later Stewart came out with his own (without the variable 10nF connected to the second transistor).
IIRC one trimmer was for the 68k at the input, another to vary the 1k5, another for the R in parallel with the inductor, plus another paralleled with the 4u(-ish) cap with one end of the cap connected to the wiper (not totally sure if I'm recalling correctly).
Teese used to goop the caps connected to the DIP switch in earlier units (but not in later--so I doubt I'm revealing some super secret here--you can find pictures on the web). They were axial ceramics with values of 240p (two 120p), 470p, 820p, 1n5, 2n2, 4n7, 10n, 22n, and 47n (plus two trim caps (100p?). From what I gathered they didn't need to be that exacting in tolerance. (If anyone tries putting in rotary switch or whatever to play with that 10nF value I very strongly recommend adding pop suppression Rs because hearing the pop when going direct is seriously brutal on your ears.)
This page used to be up on the Teese site and the tunings (not all) seemed to be based on a 20% tol. 10nF though maybe pointing out the obvious) :
https://web.archive.org/web/20060908041215/www.realmccoycustom.com/RMC3TUNING.htm
Oh, also the other alu electro is probably for a power supply filter--they seem to be (something like) 1k(-ish) plus 100u or 220u.
Also, (reading some of the comments by Gus, RM, etc.) seems like a bit of a crapshoot unless things were selected or tweaked esp. for the mass-produced ones.
(dang blasted leaking memory cells...) yes that 470R for Q1 is varied in (Fulltone?) I vaguely recall fixed R in parallel with a trim pot. So another parameter to play with.