I would like to enlarge a 5/8 inch hole in a billet aluminum pulley and pulley spacers to 3/4 inch. If I get a good quality 3/4" bit and enlarge the hole on a drill press, am I risking a centering issue with the pulley on the shaft? Is there one special drill bit that works better than another? Am I better off having a machine shop do it?  This is the dual belt project on my Y blocks with using the double groove dampner with double groove alternator pulley and getting a water pump pulley that will work. I have a drill press.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's