I have seen axle mounted rack and pinion steering for semi trucks.. Well not actually on the truck, but at a trade show. I would expect to see them become more popular as they are tested, and become accepted by truckers.
But for a small rack and pinion to be mounted on the axle for our trucks I don't think it's a good idea. If there were a factory setup that could be adapted I may change my mind, but any homemade setup I would be hesitant.
Perhaps if you really want to make it happen you can use the slip joint and or steering shaft from the semi truck sized unit, It can't be but so much bigger then needed on a smaller vehicle, as a person's arms are only so strong.
Grigg
