A little update.
I pulled the rear axle (a while ago). Turns out that the posi tag was ruse and the ratio is a 3:36. Finally getting around to disassembly, cleaning and rebuilding as necessary. The insides look fine, so off to good start.
Found a couple of kinks in the frame due to a front end accident sometime in the truck's lifetime. :-( Not happy about that and it's at a local truck frame straightening shop. Their specialty is big boy trucks/rigs but he does antique car/truck frames when things are slow. He just finished a '55 truck frame for his buddy and now he's finishing up mine. Not a bad price either, $750 to ensure that it will go down the road straight. :-)
-Mike34