MrBen, thanks for the post. I had the transmission removed from its mounts the other day to check the mounting studs, but have yet to disassemble it. That could be my next step and probably should have done it while I had taken it that far.

I am well versed in the power drill/alignment procedures at this point. The main issue is that even when aligned by the notches on the trans or when measuring off a hard point- the driver side clamshell arm is hyperextending when it reaches its most rearward travel and will sit at a different elevation than passenger side during operation (pictured in last YouTube video).

Took a look into the transmission and it is still the original one from 1999 with a stout metal gear. Everything looked operational. I struggled to refit the transmission the other day and it gave me difficulty removing today, so I took a closer look at the metal studs from the body that it attaches to.

They are canted upward a decent amount, but hard to tell to what degree they should be from factory. I will start working on taking apart the functional passenger side to see if that gives me an idea. And if I come up empty, convert to manual operations, as that is the last idea and conceivable deviation that I can come up with.

https://www.youtube.com/watch?v=-J-Na1DyANI

The functional passenger side transmission easily slid off it's mounting studs and they measured level- unlike the studs on the driver side. I slid a deep 8mm socket over the driver side studs and used a 2x4 and mini sledge to hammer them until level. Measure, hit, measure so that I didn't over do it. In the end it was hard to align the 3 mounting points within a 3D space and it went back together much easier than it came apart, but the mounting studs were still not just right and the movement remained off.

I made the decision to call it quits and convert to manual ops. The cost-benefit on continuing to allocate time toward aligning he clamshell arms just wasn't adding up and the simplicity of manual operations will hopefully ensure reliability on long road trips far from my tools/spare parts. I still need to twist the clamshell back and hopefully will be good to go.