Not many people have had luck mixing straight axles and rack and pinion. It's nearly impossible to not have steering geometry issues, unless the rack is mounted to the axle, and then a splined slip column used. if it's got an axle already, I'd dump the rack and go to a traditional tierod and steering box.It's got a solid axle(original Crosley) with the rack mounted in front of it. They have been running it like that for some time. Don't know how much of a bump stear problem it would have. The king pins were so sloppy in it I doubt that bump stear would have shown up. I rebuilt the front axle with new bushings and model T kingpins which was the right size. We cut the kingpins off and threaded each end for lock nuts and beefed up the axle. The front spindles I think are reworked Toyota PU to get the disk brakes.