So I finished fixing tractor. Not before taking a few trips.
A few points:
My tractor is a 2010 1700 hrs. Was rattling pretty good. The fix is on driven pulley. Which is the upper one. The outer sheave will need nothing.
Important to note their are no bushings in the original inner sheave, just steel on steel. Their was no sign of grease left just powder. If you order new bushings they will not fit in the original inner sheave.
There is an updated sheave with the bushings included for around $700. Does not come with seals or backup rings or snap rings.
The shaft was wore enough I replaced it ($800) and the two bearings, one of which is subbed up to a new part number. My bearings seemed to both be good. But I replaced them both.
This is neither a technical or complicated job. However I encountered one problem. I greased splines on shaft and inside cavity of sheave with a little too much of the recommended grease from Deere because of the fact that they seem to dry out quick. I was conscious not to pack sheave full of grease but when I bolted outer sheave on to shaft the inner sheave pushed grease out both seals and bent both snap rings

. Which I should have caught when bolting together. So basically you can only grease the splines good and put it together.
As mentioned mine was making enough noise we started to worry about it flying apart. It would have ran a long time and would have to get really bad before it self destructed because the outer sheave is bolted solid to the shaft.
An important note is that the sheaves can be removed quite easily for inspection and could be greased periodically. The operator manual details fan belt replacement. I would place a big piece of cardboard between rad and fan first. Follow those procedures remove the 3 bolts they say to loosen up to 1 inch, and remove outer sheave, pull fan out right hand side and remove inner sheave.