2001 Cadillac EL Dorado Changing Lights

This procedure is for removal of rear license plate pocket, you should be able to access bulbs from there. You will need to first remove the license plate, and the trim cover mention is at the bottom of the pocket-three screws.
Rear License Plate Pocket Replacement (VJ6)
Removal Procedure

Open the rear compartment.
Remove the fasteners from the license plate pocket trim cover.
Remove the trim cover.

Remove the fasteners which retain the license plate pocket to the rear compartment lid.
Disconnect the wiring retainers.
Disconnect the bulb sockets for the reverse lamps and the license plate lamps.
Carefully remove the license plate pocket.
Installation Procedure
Connect the bulb sockets to the reverse lamps and the license lamps.
Install the wiring harness retainers. Ensure that the routing of the wiring harness does not interfere with the fasteners or allow the wires to be pinched during installation.

Important: Ensure sealer is present at the fastener locations in order to prevent water from entering the rear compartment.

Position the license plate pocket to the rear compartment lid.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install the fasteners which retain the license plate pocket to the rear compartment lid.
Tighten
Tighten the fasteners to 1 N Â m (9 lb in).

Install the license plate pocket trim cover.
Install the fasteners.
Tighten
Tighten the fasteners to 2 N Â m (18 lb in).

Close the rear compartment.