The torsion bars are the springs for the front suspension. The ride height adjustment bolts are 27mm as mentioned, and should be on a crossmember midway between the wheels on each side, near the frame rail.

Definitely start hitting the threads on that bolt with penetrating oil of some kind. That rust will make the bolt quite difficult to turn at first, you will likely need the leverage of a long breaker bar to get it started.

Steve Carlson - 95 Trooper LS expo rig
Serenity now!