Maintenance first. As stated, start with alignment, it is cheap. If you have not rebuilt your knuckles, throw new bearings in it. Are the tie rod ends and ball joints in good condition? How about the steering damper?
Once done with that, if money is a concern, either get an adjustable panhard bar or get the Delta panhard lift bracket. You will see a very noticeable difference with this addition for not a lot of money. Finally, caster is the criminal for robbing the 80 of a good road manners. Get it fixed, don't cheap out on it. I added the delta arms and, wow, what a difference!
Running the rig between Flagstaff and Phoenix, especially going down hill, was much more of a struggle than I fully understood until adding the bracket and arms. I did not realize how much attention (effort) I was paying to what it was doing before with the constant steering corrections to keep it pointing strait. Adding the delta products was a life changer and probably the best mods I have done to the rig after it was lifted. So much more relaxed when I arrived to the destination after that, life changing.
Also, I went for a bolt on solution for the arms, the drop brackets are nice but, going back or changing later, is a PITA. Oh, and stay away from the caster correction bushings, don't work, not worth it.