According to the manuals, the '49-'54 Passenger and '47-'54 Truck axles use the same mounting system, and the U-joint/torque tube mountng is the same as well. Gearing on the Passenger axles will vary sepending on year and transmission. manual trans '49-'52 is 4.10, just like the Truck, '53/'54 uses 3.70 with manual. The '51-'54 Powerglide cars had the 3.55. The may be an issue with length, as the Passenger wheelbase is 115" vs the 116" of the Truck. Thsi may cause the rear wheels (which are already 2" forward of center) to be moved up an inch. This might cause problems with the axle mounts as well.
Unless you're dead set on 5 lug, the easiest way would be to stick with the stock axle, install a set of 3.55 gears from Patrick's for better highway driving, and use the 6 lug version of the front disk conversion.
