At the end of the pwer steering box there looks to be a grounding strap ..What does it ground..?
Since I am replacing the PS box the new one does not have the short nub on the end of the shaft..do I have the wrong one?One parts store asked if I had the small or large input shaft?

Shannon
There is a short ground strap that goes from one side of the ragjoint to the other. Positively grounds the column to the chassis.

Production 1971 Chevelle power steering gears had a 13/16 diameter input shaft. In 1977, all GM power steering gears were changed to 3/4 diameter shafts.

the strap is not needed if you new rag joint has wire mesh molded into it.