You would benefit greatly from a power steering test. Get some light, get under the front of the rig, have someone start it up and turn the steering wheel back and forth from about 11-1 fairly rapidly.
You watch and touch every joint that moves when that is happening. Put a thumb on the ball joint or inner C, forefinger goes on the other part that is moving. Do that as well for the rest of the joints. Check the TRE's and make sure the body isn't popping up and down on the pin. Look and feel for any movement that should not be there. Look at the joint in the axle side trackbar and watch how far it moves relative to the bolt. Check all the threaded connections with jam nuts, they generally wiggle to show they are loose.
When done watch the input shaft on the steering gear. The rotational input from it should very closely match the output rotation of the sector shaft where the pitman bolts on.
If it doesn't, then you need a new gear. A simple test is to finish ruining the steering gear by adjusting the lash tighter at the adjuster. If that tightens up the steering and slows down some of the bad habits that give you the impression of diminished ride quality, then it really is time for a new steering gear.
I don't know that I have any left but I can check to see if I have a lower mileage stock replacement if you want to pay shipping to tide you over and test if that was it before you jump into the steering parts black hole and spend a small fortune.
