The Ford Service Book makes no mention of the earlier style torque tubes. I just finished up one today, and here is what I'd like to share. First of all, my drive shaft was ok, all of it. It's the only one I've worked on that didn't need the inner 2596 d.s. roller bearing sleeve replaced. I miked all the ball bearings in the thrust bearing assy, and they were ok. One was missing, so I replaced it. I packed it well with wheel bearing grease. The outer bearing sleeve was slightly worn, so I replaced it with a NOS one, and also replace the bearing which was worn .002 with a NOS one of those. I tapped in the thrust bearing until it seated against the outer sleeve. Since none of the parts I used came from the same car, it was a bit of a challenge to get the parts to cooperate, but after many disassemblies, it got easier each time. To hold the roller bearing assembly tight agains the rear of the torque tube I used two LATE d.s. retainer bolts put in backwards, as I was fitting the NOS driveshaft front bushing. The bore of that bushing didn't requre reaming, but did require a lot of facing with a Stevens facing tool. After at least a dozen tries, I was able to slip the u-joint pin all the way through. I failed to mention that I had already installed the d.s. distance plate before installing the bearing.
I don't think I could ever make any money doing this stuff. It just takes too much time.
One thing I failed to mention, is the driveshaft required a NOS pinion key. I also used an excellent used ring and pinion set for this differential. The u-joint that was in the car was still in very nice shape, so I was able to re-use it. I could have used one of Johns new setups, but I still like doing it the way Ford did.
Do you recall the clearance between your drive shaft OD and the torque tube upper bushing ID?
I used a NOS babbit front bushing. It did not need reaming, although I ran a Stevens reamer through it anyway. I did have to face a fair amount off the front of it to get the proper clearance for the U-Joint.