Stereo & Electronics - new gauge cluster question.

i am thinking about switching the interior of my 2001 trans am to blue. So i will be buying a camaro cluster (if anyone has one let me know). But im curious as to when i install the new gauge will the odometer stay the same for my car or will it read from the other car? OR is it just the overlay i need and i wont even need to worry about the odometer? help me out guys
thanks