My 382 w/stellings boxes is hard on drives. There is no "drive coupler" on the back of the crank. The short driveshaft bolts directly to the crank. Has anyone designed a "cushioned tube driveline". Any Thoughts??

Easy solution...Teague stocks a shock absorbing disc that is approximately 1" X 6" that goes between the steel disc from Stellings and the flywheel. Its main use is in high torque applications like diesel powered cruisers. I think they are about $200 ea. You may be able to install it without having to shorten your drive shaft

The product Sprague is referring to above is the Globe "drivesaver" coupler. I believe there have been previous threads about this. Try a search on drivesaver.

Not needed, Teague hasn't sold one in years.

I have Stellings extension boxes on my ride and have used the "Drive Saver" which is like a hard plastic type of material that bolts right on the flywheel coupler. Keep in mind that these Drive Savers will change the angle of your driveshafts because they shorten the length.
I bought mine from Teague Marine about 4-5 years ago----who knows, maybe it was me who was the last to buy them from Teague. I eventually removed the drive savers two years ago---it probably would have been okay, but I didn't like the driveshaft angle. Engines were 540cid Naturally Aspirated 680hp at the time.

If you decide to move forward, here is the Globe website, they have numerous distributors.
www.globerubberworks.com The part # was MRD504PR.

I'm glad you took them off!

You can run the Imco torsion shaft with a standard Merc coupler instead of the Stellings shaft/joints/bearing/etc. Drawback is that the box has to be mounted in the neutral position and cant be raised or lowered with the straight shaft.