When I removed the steering box hoping to remove excess play by adjustment, I found that the weld securing the geared quadrant to the steering arm had broken all the way round.
I have since ground away the old weld and redone. It might be worth checking to see if there are any cracks/fractures in your tractors steering box.
Chris
Steering box issues
Moderator: hot66
Steering box issues
Porsche - Diesel, the next most affordable Classic