See if you can get a Programmer to make an Input solution... that takes the Optical wheels signals, and
translates them into a limited left and right range of Pot Values. If you go past the maximum pot values...
the program would keep putting the values back to the maximum values... so they could not go any further.
The other option, is to make a Cam-Switchable hardware solution. Where you can engage or disengage
the optical or pot from the drive shaft.
Yet another option, could be to make a plug-in, pot based Paddle controller... that you use instead of the
Optical wheels.