Bullitt Wheels - How to open up bore?

@Haney - My bit was not stepped as you typed and (my poor memory) it was actually 2.5" diameter I just went and checked. I did notice that with so little clearance in the centerhole for the bit that I had to really keep the stone pressed hard against the rim. A couple of times in the beginning, before I got the hang of it, the stone would start to bounce around the center hole if I relaxed my tension. In addition I found that the process was much more friendly when using my slower (1800? RPM) drill motor rather than my die grinder (3500 RPM). About a .100 total equates to about .050 from the circumference. I had a broken rotor and used the cast bearing center area as a go/no go gauge that, when put up to the wheel, showed me there was not that much to remove. I also used it during the grinding process to limit excess material removal. I'll add that the first set of these I did for someone else and they've had zero issues with their use over the last 5 years and about 25K miles or so while driving very enthusiastically and banging gears leaving every stoplight.