I have heard that the hub thickness isn't sufficient to remove that much material without either seriously weakening the hub, or that you can actually cut into "air" if it was machined thin enough, originally... in either case, not a good idea.
i wasn't real sure about that,i thought the pilot was solid.i've done it the other way....new engine/old trans,and i went to a machine shop and the guy made me a ring that made up the difference.....took five minutes and worked great.i was just hoping it could be that easy for this guy.