I'm having problems with the balance of my clutch/flywheel assembly and am sending the unit back to Spec. My mechanic removed the clutch and I noticed on the back center of the flywheel a part that I didn't recognize. Is this part of the clutch/flywheel assembly or should it be removed before sending the clutch back? I don't remember it when first receiving the clutch. The part is circled below:

That's supposed to be there. It's been on every one of my clutches with the exception of the one that blew up. It fell out of that clutch.

No worries.

Thanks.