I got the 3MT blank arbors today. It's a way of making a repeatable on center fixture in my lathe. I'll be turning the stub down for a precise fit inside clutch bell roller bearing bore. Bolt down the middle to secure it all. Everything should be turned off the roller bearing bore. Will true up the outside. I realize this isn't balancing, but I'm moving in that direction. I have a very sensitive Hi-Point balance fully capable balancing a 6mm nut. I could fit the clutch bell on it and take it further if I wanted. For now, I just want to get rid of the extra metal that is not concentric with the bore. Trying to get rid of the strong vibration at speedo 35mph. Very curious if this will make a difference or if the vibration is crank related.