Cadillac 1996 DeVille Owner's Manual page 294

3. Replace the bulb.
Reverse the steps to reassemble the stoplamp assembly.
Taillamp
1. Loosen the upper Tom@ screw, but don't remove it.
2. Gently tilt the top portion of the taillamp housing to
access the bulb sockets. If you can't access the lower
bulb socket, remove the taillamp housing completely.
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