While I don't own an FJ/FZJ80 (yet), I have started looking at them and have pretty much decided to get rid of the 4Runner ('95) and, instead get an '80 to build up. I was just, literally, starting work on the 4Runner, when several things caught my eye about the '80's and I've decided that an '80 would be much better for me, what I want to do, and how I want to build it.
Anyway:
- Regarding the drop bracket(s) for the trackbars (panhard). That's exactly the
opposite of what should be done (the drop brackets are available for the 4Runners also).
The axle end of the trackbar needs to be raised up,
not dropping the frame end.
- Poly really has no place in our suspensions. Rubber bushings are far better (maybe discounted the wear rate, but everything else) and rod ends (heims) or even better, J-Joints are the only way(s) to go.
Poly is too stiff and, as such, transmits too much twisting force to the attaching brackets. Rubber gives and, of course, the heims or J-Joints have a lot of "flex".
I have seen trackbar mounting brackets ripped (me for instance

by the use of poly bushings.
If you look and how the axle moves (side view) as it articulates, you'll see that there are several force vectors involved, and poly doesn't address all of them.
- Lastly, leaving the jamb nut loose is simply asking for trouble. The threads will wear and cause lots of looseness and noise, and possibly finally break.

Fred