Tighten up steering = $0.00 plus one cold can of beer for the steering wheel twiddler, plus a quarter bucket of sweat loosening up the lock nut and tweaking the worm and sector clearance, taking up the slack in most steering boxes. Get it too tight and it wont' self straighten coming out of corners.

Idler arm bushings are about $4 each, plus another half bucket of sweat, and maybe another beer to the guy with a pickle fork tool to seperate the steering joints on the idler arm (not strictly required, but eliminates a lot of kinking around to pull the idler arm shaft out of the bracket to get at the bushings.

It's been well documented that going up from the 235/75/15's to 31's is getting into the area where you need a little more caster, and you need to set the camber almost flat. The smaller stock tires ride with a little tilt out at the top of the tire, and the bigger tires really like to run perpendicular for best wear and traction. The added caster helps hold the steering centered on the road, for a stronger on center feel, perfect for long highway trips, slightly more tiring if you do a lot of steering, like a very curvy road, but not bad at all.

Any real steering stabilizer is valved so that it has NO EFFECT at normal steering wheel rotation speeds, and no stabilizing effect at all, only working when the wheen moves at speeds your hand can't duplicate. Like severe bump steer. It's your $5. Have fun. I might be wrong, too...

If you're dead set on doing it, you need the one with one L bracket with a Ubolt on the steering center link, and another L bracket anchored to the frame. Probably have to drill bolt holes, but you might find a way with more square Ubolts to go around a crossmember, or use existing holes.