OBS,
Welcome to the "Dark Side" of the SimV habit ;).
Take a look at some of the past threads and links on rudder pedal design.... there is lots of info here.
You can hook up other potentiometers to the SAME connections that the original ones had on the pcb (printed circuit board) ..... but you need to have the SAME VALUE of resistance as the originals. Take care in soldering... the joystick boards are typically pretty "cheap". Don't use too much heat.
The potentiometer resistance is measured in Ohms. A simple cheapie multimeter (from someplace like Radio Shack) will let you test the existing pots to see what maximum value they are/were. (Handy tools for simpit use.) Some joysticks use 10 K Ohm pots. Some use 100 K Ohm ones. Some use other values.
There are typically three wiring connections on a potentiometer back to the pcb. One is the common side, one is a fixed value that is the total resistance of the pot that doesn't change at all, and one is the variable leg....that goes from zero Ohms to some value. Make sure that you get the connections right. It typically won't hurt anything in this application.... it just won't work.

Good luck.
best,
..................john

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