Since the rack & pinion is mounted on the axle, the shaft that connects it to the steering column must constantly change length and angle to compensate for front axle movement up and down, plus body lean. It's almost impossible to keep the slip coupling aligned properly and lubricated sufficiently to keep it from binding and/or wearing out rapidly. I guess it's OK on a trailer queen that gets hauled to car shows and spends very little time on the road, but that steering system would be the absolute last choice I'd make for a daily driver. If you want to keep the straight axle (a very good idea, IMHO), why not mount a power-assisted modern steering box on the left frame rail ahead of the axle? It's a simple fix for anyone with a pretty good knowledge of geometry and welding, and much more durable and reliable than the R&P system. I really have a problem with using components for subcompact cars on pickup-sized vehicles.
Jerry

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