Didn't read too far back, but you try getting your tires balanced or rotating them?
I eliminated tires in multiple different ways prior to the rear end repairs, so it’s possible that they are contributing to the remaining vibration. I think I am working through multiple independent issues with overlapping symptoms. The worst of the vibrations is resolved, but now the secondary issue needs to be fixed.
My time when I’m motivated has been limited, so it’ll be a few weeks before I dig into it again.