SOLUTION:
Ok, I figured out the problem. 1989 b2’s are the only year where the J spring code is an option. These springs — 929-206 — are beefier, heavier, and have more static arc. They also come with the locating pin on the top to be installed in the spring under configuration. I had to flip that to install. Now the rear sag has been corrected!
All of the auto parts websites, except for one random place, didn’t even offer that spring as an option. it was total luck that I noticed the discrepancy.
Funny enough, those springs are explorer springs, so I could’ve picked some up at the junkyard for almost nothing. Instead, I got brand new dorman springs for way too much money. And because I got them from Parts Geek, I can’t return them without paying my own return shipping for over $100…
at least I can return the regular bronco 2 springs that I just removed.
thank you all for your help.
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