OK, just for the halibut, I've attached pics of what I consider to the the best tool for the job of enlarging the centerbore. This particular flycutter is adjustable from 2"-3". 

The downside is the 1/2" chuck usually only come on large mills. The average home shop usually makes do with a drill press.

The Listserver will strip my attachments so only Jeff the Phoneman will get it. Picasa doesn't yet support uploading from a mobile phone (no pun or phone intended). I will eventually post online for others who want to see the photos.

BenT
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