I finally got my car into the dealer today for some work and spoke with a pretty reputable tech on the cluster issues. Basically his explanation was they could not sync the miles due to some regulations with fca on tampering with a vehicles odometer. So do not swap the clusters and drive a crazy amount of miles because if you swap back, there's no way (from what he said) to re sync the mileage to what it's supposed to be on the original cluster. And in regards to the shift indicator, cruise control and the other odd issues, those are due to the different bcm modules that were used in 11 vs 12+ chargers. So to correct those you'd have to swap bcm's with an 12+ to get the things to work correctly. If you really wanted the new cluster style you have to drop off your car at the dealer and have them order a new blank cluster and install it so it will display the correct millage.