I do not know about putting a Patrick's 3.55 kit into a '54 rear end, but an earlier rear end would not work with a '54 Hydra-Matic transmission, without shortening the drive-shaft and torque-tube.
Maybe the '54 Hydra-Matic torque-tube and driveshaft could be used on the earlier 1/2 ton rear end?
I agree with djed50 - just drive it. This combination of rear end (4-speed automatic) and torque-tube rearend is uncommon - a good conversation piece and not a bad ride.
