Larry,

I think the adjustment Fred is speaking of is the bottom bearing preload for the worm gear. If this were the cause of your problem, it might be noticeable in the steering wheel itself. A gross misadjustment here would force the whole shaft up and down...trying to shove it into your chest or pull it away from you. As you turn the wheel back and forth, you would see any gap between the wheel and turnsignal cup get larger, or diminish. I think this is how it works.

Stuart