After a bit of googling, I found the Federal Standard Code for the grey paint used on knobs. Humbrol #129 looks pretty good!
First coat on, a couple more coats will finish them off nicely!
Home of TA-4k Sim NZ6258
Sponsored by Boeing?
Well.. I’m cheating a bit… I’m painting knobs for my Douglas sim, and I’m purely guessing the knobs would have been *roughly* the same colour!