350 U one way power steering 2nd rebuild

If you've not seen my previous post on this, I purchased this tractor and PS only works turning right.(I recall right). I removed and tore down. I replaced rusted damaged bearings all orings and the gear shaft pivot pin that runs up and down the spiral cam tube. I didn't replace the large oring in the hydraulic cylinder. The race,both shafts and main bearings and valve spool looked good. Some pitting on the upper steering shaft. There are dings in the spiral cam tube. See pics.
I reattached the cleaned, rebuilt assembly to the tractor. The loader and rear remotes worked great. Steering still one way. After about 2 mins. hydraulic fluid began leaking above and below the valve spool.
After removing and rechecking the entire unit I've further touched up some of the pitted and dinged areas and replaced the oring in the hydraulic cylinder. I have a couple of questions and concerns prior to reassembling.
1. I was surprised at the amount of wear on the pivot pin. (See pic) The tractor only ran for a few minutes. When rebuilding I did turn the wheel dozens of times to make certain everything was working and turned it in the difficult direction a couple of times to see if it would loosen up when it was running briefly. The spiral cam tube showed no new wear. I have now smoothed out any rough edges on the tube.
Did I over tighten the adjustment screws? Does this sound like a clue as to why the PS only works one way?
2. According to the Reassembly instructions, the steering shaft ad measured at the steering hub is supposed to rise and fall a total of .1 to .15 inches when the steering is turned completely left to right. Mine does not seem to be rising or dropping at all. I understand in part why it's necessary and understand if there is a blockage in the passages of the valve spool it will prevent the steering from working correctly. My question is what literally causes the up and down movement? Is there a groove somewhere the shaft rides on. Am I over tightening the adjusting nut? I loosened the nut when I removed the unit and couldn't measure a change. The up and down movement seems like it's a key to the correct flow of fluid in the cylinder. I included a drawing from the manual that shows the internals of the cylinder.
Let me know what you think about these items and anything else that might be causing this issue. I have read of this one way issue occurring to others but have not read of a conclusion.
Thanks! Paul

Jim's thinking: There are 6 plungers ((active Plunger) in the assembly. These are pushing on the three centering springs. The turning of the steering wheel turns the worm the worm tries to move the stud on the arm. The stud, being connected directly to one of the two steering shafts doesn't move unless the wheels turn. This resistance to turning causes the spool to move against the centering springs either up or down the .050 based on left or right turn. If you are getting no up/down motion the active plungers may be sticking in their bores, or other blockage is causing resistance to that motion. If the plungers are free to move when disassembled, look at other features that could cause reduced/no motion up and down. The preload on the shaft bearings should be modest, not tight. The depth of the stud in the worm groove should be snugish without binding in its range. The stud should not be wearing much at this point. Was it fabricated? it is pretty hard material originally maybe case hardened. Jim

Thanks Jim. I now have a better understanding of what needs to occur to make this system work. The plungers move freely though they don't all just fall out if I tip the unit. A slight nudge is needed. I hope this is ok. It seems the centering spring would easily overcome the resistance. I cleaned them all lightly with some 600 grit. No rust just blackened in spots from heat and usage I imagine. I dipped everything in hytran prior to assembling. I do have a couple of questions.
1. What do you mean by pre load on the shaft bearings.? How and when do I do this?
2. What exactly is moving up and down, shaft itself?
3. I was also surprised that the sector pin was worn. It was only used manually when I tested during first reassembly and for the few minutes the tractor was running. I purchased that from Steiner. (Will be more conscious about purchasing from this site.) I had a local welder remove old and install new. It does not rotate. I'm hoping it is still fit to do the job.
I'm currently struggling to remove the lock nut on the cylinder piston rod (see 2nd pic) so I can replace the small oring in there. I'm putting the race, protected with a cloth, in the vice. I'm concerned I'm going to twist or break the piston rod or some other part of that assembly. I hate to skip that oring if it might be part of my problem.
3. What exactly it's moving up and down the .05, is it the steering shaft?.
As always thanks for the help. Paul
<img ps
Sorry for the duplicate pics
I don't know how to delete them. Thanks
src=https://www.yesterdaystractors.com/cvphotos/cvphoto101331.jpg>

The entire internal parts move up and down. From the Far end of the worm, to, and including, the steering wheel. It moves up against the centering springs pressure as the Stud stays still and the worm ramps up the temporarily stationary stud. Turning the other way the stud is stationary, and the worm is pulled down (again) compressing the other active plugs against spring pressure. both up from center, and down from center channel oil pressure to the push side of the piston, and release it from the opposite side, powering the movement of the rack that drives the arms.
The preload is the amount of tightness of the thrust bearing adjusting nut. Ball thrust bearings like snugness to operate smoothly, but not tightness. The shaft should turn by hand with no play.
The cylinder nut can be removed with a strap wrench around the piston, or with an impact wrench while holding the assembly in your hands to avoid impact damage. Jim

Thanks Jim. Great explanation and the picture is clearer.
All appears as it should at this point. With the unit half assembled and the adjusting nut hand tight when I turn the steering shaft and look closely at the plungers, all 3 move up and down. They are not yet moving straight up and down as the wheel is turned completely left to right but they are all independently moving so I'm hopeful they are free to move their respective bores
There is one area I'm concerned with based on your explanation that everything should move. The picture below is of the inner thrust bearing race (18)that sits inside the valve adapter (#30) above the needle bearing (#16.). I had to press this race in place with my fingers for it to seat. It has an oring seal on the outside and in my head it's job is to form a tight seal so it should not move. Can you please let me know whether that race should also move or ok staying firmly in place.
Fyi, I was able to finally remove the lock nut from hydraulic cylinder shaft and replace the small oring (#60). Thanks for your help. Paul

#18 is a part of the moving assembly. It is a Dagwood sandwich of parts between the end toward the worm (a collar) and the preload adjusting nut toward the steering wheel. There are O-rings in both 18, shown, and the other 18 near the preload nut. they do seal, but also move in there bore .050 each way. Finger pressure is required to install, but not relevant to operation. Jim