My Cadillac has a number "1" or "2" on the key fob and the car knows which driver by the fob. I am not sure if the 2000 DV had fobs but if all you have are buttons on the door with a "1" and "2" then you put the button in program mode, set all of your settings, like seat and wheel position and pedal position then select the "1" or the "2" to program those setting for that driver. The manual should detail this pretty well.
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