Yep, I understand that. My problem is a customer brought one in for me to grind and wanted to know how much has already been taken off of it. My AERA flywheel spec book does not give me any information on what the flywheel was when new, or a discard thickness. Other than to say it looks ok to cut, I really don't have anything to go on. I meant to post the casting # when I was at work and didn't get it, so I will post one up in the morning if it will help. Pretty sure it is a early to mid 70's small block. Flywheel casting # is 2264598.

Thanks!