I've had the same problem for a year. I replaced the tie rods, idler and pitman arms, gear box, and the center link. Still had a lot of slop in the steering wheel.
Last weekend, I bought a Rag Joint repair kit from oreilly's. I removed the intermediate steering shaft in about 10 minutes. It only took me 4 hours to get the rivets drilled out and popped off, then another trip the store for grade 8 bolts, and about 10 minutes to re-assemble.
Drives like a new truck. I am not constantly correcting when driving on the highway anymore.
Supposedly, you can take a lower shaft from a 90's Cherokee and drop it right in. It uses U-Joints instead of a rag joint, but I don't have any good junk yards around me to test that theory out.
my .02