I am swapping engine and with the engine out I am changing the clutch. I want to get the flywheel resurfaced but I don't know how much life is left on it. It has 490k miles on it but the previous owner drove mostly on the highway. There is a fairly worn down but i don't know how far it can be worn down till it is no longer good. So what I am asking is how far can the sirface of the flywheel be resurfaced down to or how to know how much life is left in my flywheel.