On a odd resort, you could also make an entirely foot Pedal operated system, where left foot operates brake/throttle and right foot operates left & right. It would still be tricky to learn, but its an extreme alternative if the one remaining hand cant operate controls well.
You could also also add extra pedals to adjust any trim Options. But if you do go via a pedal route, I would suggest buying some sim racing pedals, that way all you really have to do is reroute the wiring to a transmitter