******power steering pump shaft "hub plug"*******

After powder coating the parts, I bolted the power steering pump back on the bracket and pressed the pulley back on the pump shaft per the shop manual directions. After getting the pulley flush on the shaft, I referred back to the manual which instructed me to put the "HUB PLUG" back on the power steering shaft.
Someone please advise what the "HUB PLUG" is & what it looks like. I assume this might be something to hold the pulley on the shaft??????, but I do not see the need for this since the pulley goes on so tight.
Thanks for any help or guidance.


