encased driveshaft?

I would definitely pick up a TSM as it will come in handy. There is a lot on that car that is not like muscle cars you have dealt with.

The correct term for the type of axle is torque tube.

The reason why you may need to obtain a TSM, is that not only it Is different, there are some key things to check on for maintenance. The TSM can assist with how to properly replace and adjust once something is taken apart.

Put a want request in our wanted section for your year on a TSM, as there are members here who have some for sale.

They were built like a modern 2017 Corvette.....one piece drive line, very advanced for their time!

HA!  Thanks.  Will do.

That's pretty much it 6768togues! I always use a floor jack to jack the rear end up, from the back. Put jack stands under the body in front of the tires (on the jack pads), then TAKE THE WHEELS OFF. Once everything else is disconnected (brake line, park brake, panhard rod, shocks... and the four bolts holding TT to trans) just slide it back on the floor jack. With the wheels off you let the jack down and don't have to jack the body up so high. With stock width tire you can probably slide it back far enough to drop the TT with the wheels in the wheel wells, I don't recall. 

The front yoke on front is double ended, so will pull off the shaft as well as out of the trans. Just a slip joint on the rear at the pinion shaft. Six cylinder cars used a single u-joint and a solid shaft (like an axle shaft) with a center bearing to prevent "whipping" inside the tube. If you take it loose from the axle end the tube and shaft will come off. The shaft will pull out from the front of the tube with the bearing. It's been a long time in there, so the bearing may not pull out easy. I wouldn't pull it at all unless I had to, don't want to risk damaging that bearing! Won't hurt to pull shaft/tube off though. No need unless you're leaking diff oil from the front seal of need to work on the rear axle though. The u-joint is most likely fine -- I've pulled 100K+ units apart to find the u-joint as tight as the day iut was put on. Protected from dust and water inside the tube.

V-8s use a double Cardan (double u-joint) constant velocity joint. It has a centering pin and spring mechanism to keep it from flopping around in the center section. Unfortunately they wear after 50 years or so and there aren't many rebuild kits (if any). That type joint was used by Lincoln in the early 60s also, but both Lincoln and Rambler only used them for 4-5 years, then they disappeared. The V-8 shaft is different though -- uses a solid back half with a tubular front half (in front of the centering bearing) . This makes it relatively easy for a driveshaft shop to cut the front part and lengthen for a single u-joint -- which works fine. 56-62 Rambler V-8 cars used a single u-joint, only the 63-66 models used the CV joint.

Thanks, Frank.  You seem to know a lot of stuff.  I'm having the flywheel resurfaced, but can't seem to find a clutch kit anywhere for this.  In fact, I suspect the one that was in there may be wrong.  I can find kits everywhere for V8s, but haven't found one anywhere for the 3.8.  Any thoughts?