yeah I understand all the geometry you described, I did take my time setting it up and moved the entire thing through it's full travel range making sure nothing bound because I was concerned about the arc from the panhard, but it travelled fine.
Famous last words of course, because at the end of the day it clearly wasn't happy there and broke free.
Anyway, that thing will be history once my eye bolts arrive to hook up to my bed and I get that thing lifted.