It would be a fairly easy conversion either way. There is no appreciable difference between the two years other than a linkage change in early 55 to help eliminate one of the sticking in park problems. Shift quadrant spacing is the same although the ind,icators are different so the electric assy would work. There is a small difference in the upper steering column internals where the PB arm assy mounts which can be modified but as you mentioned, most parts from a PB donor need to be found.