P.S........I'm hoping that cleaning the threads up on the hinge bolt / jaw works, as I really wouldn't want to be using threadlock there. I'd rather avoid it on the stock fasteners, too, so hoping the future de-tune works.

I still have the old barrel latch so might grind the end off that a little more and see if it takes care of the vertical play.

I take your point re resonance / harmonics, but I think softening and slowing the cycle down would pay dividends. If it's anywhere above 10ft.lbs but super-sweet I'll be happy.