[Sean Hamilton]

Option 2. I like the bearing sandwich, but
Option 3. (PITA) If the chatter is within the old bearing then I'll be "replacing" it.

I'll be speaking to my mechanic tomorrow hopefully so I'll let you know what he thinks about the bearing sandwich idea.
When I mentioned replacing the upper bearing he didn't think it such a big issue - mentioned something about drilling and anchoring a press to the bearing face and extracting it? Or something like that without the need to remove the shaft.