The most common problem that gets mentioned with the axle-mounted R&P system is the necessity to have a "double-D" telescoping shaft bewtween the steering column in the cab and the steering gear pinion shaft. These things are notorious for binding and locking up the steering at the worst possible times. Another approach is to mount a regular Saginaw power steering box ahead of the axle and point the drag link rearward instead of its normal position. At least one of the kits designed to do that has gotten some really bad reviews on this site by professional hotrod builders who should be able to make an honest evaluation of the setup.

I believe it would be possible to rotate the front-mounted Saginaw box 90 degrees and hang the Pitman arm down parallel to the frame, and have much simpler geometry than the kit that's being offered, but I've never seen it done that way.
Jerry

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