You don't need "rack and pinion". You need to fix whatever is loose/worn out, and maybe replace the existing steering box with a box having a faster ratio, or a stiffer torsion bar, or both.
The FIRST thing I'd do is look at the rag joint. Rag joint failures are epidemic. The preferred fix is to replace the rag joint with a metal universal joint built into a replacement lower steering shaft. This is more complicated on 95-newer trucks that have a universal joint in the steering column under the dash. I don't know what the current "hot tip" is for those vehicles.
Next would be to look at the various suspension joints--ball joints, tie rod ends, idler arm and pitman arm. Assure that the front/rear sway bars (as applicable) have good bushings and links. Pickups don't have rear sway bars, SUVs do. My pickup didn't come with a front bar, either--but I put one on from a Treasure Yard vehicle.
Lastly, be sure the control arm bushings are in good condition. It's virtually guaranteed that they're wiped-out unless they've been replaced at least once since the truck was built. I prefer Polyurethane as they're SO much easier to install than rubber bushings--but others will disagree.
