why not just measure 7mm around, and use an angle die-grinder to
remove the material~
just make sure to keep the metal cooled by a stream of water, or tool coolant.

Sudhir

On Mon, Feb 1, 2010 at 13:55, C B <cunegonde.van.westfalia@gmail.com> wrote:
> Gotta enlarge the centerbores to fit the front grease caps on Cunegonde's
> new Audi rims. Before we mount the new Geolandar tires. The only quote I
> could find was over $40/rim! I don't need precision, I just need the
> centerbores enlarged about 7mm. What is the list wisdom?
>