Little gear which turns Left/Right pot:
-> 1-1/4" diameter from gear tip to gear tip
-> 28 teeth
Little gear which turns Up/Down pot:
-> 5/8" diameter from gear tip to gear tip (***)
-> 14 teeth
*** Understand that this pot is mounted inside the metal housing and this information is very hard to determine. I got a tape measure in there though and I believe I am very close with this measurement, however, I do not know how exact you want.... Basically, it is hard to look at the tape measure straight on to get an exact reading...
PS: Please note, there are other bigger gears which turn these little gears (which I listed above), which then turn the pots.....oh My!
Hope this helps,
UncleT