I don't get this part of the installation at all.

In the instructions it talks about removing the two caged bearings from the drive sprocket. What has me confused is, isn't the drive sprocket held in place while the SS shaft spins around inside of it? How does this not create metal rubbing against metal in the event that I am going over large bumps? Just seems to me like the bearings or SOMETHING should be in the drive sprocket housing to keep the shaft from scratching it all up.  

This sounds like a 32-spline kit. Isn't there a bushing? Been a while for me.  

I don't believe so. I just saw the shaft, then there was the part that says to remove the caged bearings from the inside of the sprocket assembly. It just makes me wonder because even the shaft has a hole in it under the sprocket which I would assume is pressure based. I don't understand why it is there unless it is lubricating something. Even then I don't think metal should just be touching metal and the shaft should be rotating on something? Don't know though.