Many boxes are mis-diagnosed as worn when the actual culprit is the coupling on the bottom of the steering shaft/column. They have bushes that are very common to see worn out and all the box adjusting in the world will not cure the SW slop.
Also, the end play in the box is adjustable and has to be verified/set before the top bock pressure spring adjuster is done. Tightening the top adjuster does not cure a box with endplay, it simply puts more pressure on the block.

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A Dalton