I am not trying to re-engineer the set up... The problem comes with the lack of original parts and seing if period aftermarket substitutes are workable... In this case, there is a NEAPCO u-joint around with a different lock ring and bearing cap, but looks actually even more difficult to work with in place (lock placement/sliding cap to remove joint) than the original design... Having said that, I was thinking about sliding the aftermarket u-joint (in the center) as a unit and forgoing the bolt, but I won't do it now, since I do not want any future problems... That bolt was placed in there for a reason and I don't claim to know more than the GM engineers who design it...
Following the project, you could also use this u-joint on the transmission side, BUT the issue comes with removing the old speedometer gear/finding a new speedometer gear and pressing it into the new U-joint... So back to square one. Scrounge for original parts and salvage what you can...
Your suggestion about the post makes sense, but there was so much more to discuss about the problem, I figured I keep it separate not to make the post to long and more complicated...
