'99 CLK320 Instrument Cluster

Can anyone plz tell me if I can plug a used instrument cluster in my car and drive or does it need to be taken to dealership for any reason? Pixel's on current cluster have gone bad...only have the one center readout display.
Have been told i can just swap out and drive, but also that i can't. Will taking to dealership transfer current mileage to replacement cluster? Any help will be greatly appreciated. thx...Ernie