At this point I have replaced almost every component of the driver side clamshell support system with parts off another Boxster. For whatever reason, the arm on that side still over extends aft when operating through the top-down sequence and is not level with the passenger side throughout. Both transmissions are in sequence. I checked that the 3 driver side transmission attachment nuts were snugged and everything is secure there.
The parts coming off the rear of the transmission V all rotate around a fixed point. All components from that point are in good condition/not bent and I have no ideas as to why the driver arm is not operating as it should (seen at 3 min mark in link). The V itself and ball mount were even replaced to rule them out. Any thoughts?
https://www.youtube.com/watch?v=2t0BlUGbKdk&t=6s