So why can you buy a cluster with 20xxx miles and put it on a car with 60xxx miles and have it still read 20xxx?

In talking to the Porsche dealer the service tech said a cluster can be "reset" once to match the miles on a car. I don't know if this is only on a new cluster or one with miles already on it also.

I inquired also about the ECU from the dealer. They said no to the starter turning the engine over without it, and weird, he said he didn't know about the car running with another ECU from a different car. Also got a ball park price on a new ECU, $2K and another $1K to install and match it to the car. This car is local here and they have probablly been barraged with ECU questions over the phone.