How do you replace center tail light on a 2006 Cadillac CTS?

To replace the center tail light on a 2006 Cadillac CTS, first, open the trunk and remove the access panel located on the rear compartment. Disconnect the wiring harness from the tail light assembly, then unscrew the retaining screws to remove the assembly. Replace the old bulb with a new one, reattach the assembly, and reconnect the wiring harness before securing everything back in place. Finally, test the new light to ensure it is functioning correctly.