I finally got a hold of a service tech that helped me out. It can be done at most dealers, it cost $150 and takes about 5 minutes.
The mileage history is stored in the vehicles BCM, however the gauge cluster displays the mileage that has been accumulated. If I was to swap in the cluster it would display the mileage from the last vehicle, it would also display that it needs to be programmed on the DIC. On vehicles without the DIC, the theft light would be constantly lit until programmed.
The mileage in the BCM can be read by a Tech 2 scanner which would be used to provide accurate mileage on the cluster. They would also need the VIN from the vehicle it came out of.
I called WineGardner, Bayside, Ken Dixon and Ourisman. All of which had no idea or gave me bad info. I want to say it was Crisswell (sp) on the eastern shore that helped me out.
I'm just going to order the stepper motor kit and redo the lights while I'm at it.