i made a mod for my radio and put the pots s1 and s2 on top of the sticks. i want to be able to control as many different servos on the sticks as possible, so i found this solution suited me well.
here is the stl. files for the pot holders and the attachment on the radio ( i made my attachment on the radio out of aluminum int the lathe in the end, but the printed ones work aswell.)
I wanted to change the pots and put a pair of ones that did not have the centre stop, therefor i had to find new ones. i asked radiomaster what kind of pots they used and they just said, -"you can use any 5k potentiometer, you can use 100k potentiometer, in fact, any potentiometer can be used".

however, this was not nessesary true. the first pair i bought from my electronics dealer was a pair of standard ones, still not the ceapest. these flickered terrible and also mage the front speaker make a terrible hissing noice for some reason.
I went back and bought a pair of a little bit more expensive ones, the guy in the stor said that i would probably not matter, but it for sure did.

the only information that is written on the potentiometers that is in the radio is "B103".

the rest is just pretty straight foreward, solder out the old one, solder some wires and draw them out to the sticks. Then screw on the pot-holder on the stick with a small m4 nut (witch i had to file the head of a bit to make fit), push the wires through the pot-cases and solder them. Then just push the new pots into the case and secure it with the thin nut and washer that usually is provided with potentiometers.

i printed the pot-cases on the sticks with supports
and the ones attached in the radio shell witout.