Oliver Super 55 Steering

I recently purchased my first tractor. Its an Oliver Super 55. I was getting ready to complete my first project with the tractor, brush hogging a field for a solar array, and my steering was really stiff turning to the left. It turned to the right no problem but it seemed to bind up at a certain point turning to the left. I jacked the front of the tractor up and began to work the steering wheel back and forth with no load inspecting everything. The steering loosened up and was free. I could go from lock to lock with only 1 finger on the wheel. I filled the steering box up with 90wt, it was empty, and worked it back and forth for about 20 turns. Once I had the tin back on, I tried one last time to make sure everything was all set. The steering now turns right effortlessly. It turns left until it hits center. Once it hits center it stop dead. I unbolted the tin thinking maybe it is putting pressure on the column but that didnt help.
Any idea why it would work perfect and then stop? Nothing changed, the tractor wasnt rocked or moved.
The major issue I have is that the steering wheel nut was welded to the wheel and the steering stem. I dont think I will be able to remove the steering wheel without ruining the steering stem. Currently I cannot pull the dash because of this. I would like to flush and wash out the steering box with kerosene but without pulling the dash I cant get the box off. I can access the 4 bolts that hold the steering column to the box. If I take those off will I be able to lift the column and stem and dash off the box or do the sector shafts have to be removed? I can do this while its on the tractor as well but I am worried about putting it all back together inline.

I have rebuilt steering boxes for Super 55's & 550's if you go that way---My email's open or you can call me at 903-729- 8349---Thanks
Kent Gordon
Palestine, TX

I got the steering box apart and out of the tractor. The thrust bearing above the worm ball nut is in pieces. I picked a few barrel bearings out of the box that fell out of this bearing. The main culprit is the ball nut ball bearings. They are rolling out of the ball nut. Has anyone replaced these? Whats the process for putting new ones in? Is the ball nut indexed? Does it go onto the shaft in a certain position? I am going to grind and cut the steering wheel off the shaft in order to get the shaft out of the column and the dash. Then I will work on the thrust bearing and while Im in there I will replace the top bearing. The bottom thrust bearing was in good shape so I wont replace that. All that will be left is the ball nut bearings and attaching a new wheel onto the old ground up shaft.