Ok, FOund out that I have a torque tube drive shaft on my '51 3100 Chevy, and nearly everything about it is bad. The guy doing the work wants to drop the rear end to pull it apart and find out what can be fixed/what needs replacing/etc.
Here's a recap of the problems: At about 30 miles an hour I get a very noticable shake, and at 45 its very bad. Yet when I accelerate or put a load on the drive train, it seems to fade. Only when I'm at speed or decelerating do I get a really bad shake.
I'm pretty sure I'm going to have to replace or repair the forward u-joint, but what can I expect from the Torque Tube drive shaft? Any parts that can be replaced or repaired?

Mike