There is NO SIMPLE BOLT ON thing when changing from a torque tube rear. the torque tube is pivot mounted on the axle, and an open driveline has to NOT pivot. Usually, saddles are welded to the axle which prevents it from rotating on the springs. The pinion angle has to be set proberly to both transmit power to the rear and to avoid catastrophic failure.
There has been some discussion in the past about using the 54- 59 1/2 ton differential on a earlier 1/2 ton. This is done to keep the original brakes, and axle width. The axle still has to be modified to mount solidly on the springs.
I will be using the 9 inch rear on my 1940 3/4 ton. the 1940 3/4 ton has a 6 lug axle... 8 lugs were introduced in 1946 on 3/4 tons. I was able to spec the width (61 inches), the splines (31, which is stronger than 28 splines, but not as strong as 35 splines), the lug pattern (6 on 5.5 like original), the gears, the posi, and the size of the disc brakes. The axle with disc brakes and gears cost less than it would have cost me to have a used one rebuilt. If the 4.11 gears turn out to be too low, I can swap them out for a higher set in about 30 minutes in the driveway. Parts are readily available over the counter locally, or through internet order, so there will be no long down time looking for obsolete parts.
Anyway, good luck with your project, and look in to upgrading the brakes. It isn't the way you drive, it's the way the other people drive which makes it necesarry. I put the CPP disc kit on my 59 1/2 ton, and it was worth every penny. You can really feel the difference.
John
