Due to recent questions about this, I've added a page to my site. I posted a drawing from the manual that shows the cross section of the box. It's shows how the gears are tapered. http://www.bluehandsvideo.com/steering-box-adjustment-datsun-521.html
I read the description in the manual yesterday, but I was not following it today. Basically, I just wanted to let you see a better example of what it's trying to describe in the text. I was surprised at how sensitive the adjustment was.
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