Installed 1/2" longer bolts and tightened the end links with the suspension settled. Also drained the air outta the helper bags. They had 7psi in 'em. I keep a few psi to help the softer "lowering springs". Without that, it'll wag too much if I jiggled the wheel. 7-9psi keeps it stable and planted. Went for a ~20 minute drive for groceries. I have some tools and stuff in the back for some odd jobs I'm doing, so I couldn't really huck it around any corners. I jiggled the steering wheel over 4-5 instances and it felt great! Flat and stable! So I don't need to keep any pressure in the bags now. As a bonus, this dropped it exactly 1/4" more in the rear. Also, it's ever-so-slightly softer on the bumps. I just need to get the front to match and it'd ride like a Cadillac but handle great and not have any dangerous floating.
When testing, I heard a bumping but thought it was something I had in the cargo hold knocking around. On the way home, it dawned on me that I never fully tightened those new end link bolts. They were close, but not fully tightened and had enough slack for the washers to jiggle. I tightened them then saw where sound was coming from. The RH side of the bar is hitting the frame side panhard mount. I really don't have much room to shift it even further to the right and that'd require custom end links. It's not an axle off-centering issue. Actually, the axle is slightly off center in the direction that is helping this interference. The simple solution is to trim the panhard mount. I'd pie cut the two vertical walls and roll the interfering back wall inward, more closely following the bushing of the panhard bar.
The passenger side showing the bar hitting the panhard mount:
My proposed fix. Cut out the areas marked in red, roll that back piece in to close the gap then weld it together:
