The sockets for the lamps are removed by twisting about 1/3 of a turn. It may not feel like they come out this way, mine were really tight, but once they broke loose they came out easily. If the wire is in your way, it unplugs from the socket by pressing the tab on the side of the plug.
In hindsight, if I had known all of this ahead of time, it may be possible to remove some of the clips, then flex the cover enough to reach the sockets from the sides, however, if your sockets are as tough to twist out as mine were, it is a lot easier with the cover all the way off.
when you replace the trim clips, hold the clip by the center piece so that it is fully retracted, insert the clip, press the center in and while holding the outer rim, turn the center a little with a phillips screwdriver till it clicks.
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Open the trunk to the Toyota Camry. Remove the interior trunk liner from the back of the vehicle. Use a Phillips screwdriver to twist the small center screw from the middle of the plastic fastener. The screw will come up about 1/4 of an inch and then you can pry the entire fastener/plug from the predrilled hole. Remove enough fasteners to allow you to get to the license plate light assembly.
Turn the license plate light socket counterclockwise about a quarter turn to release it. They may be tight, but this is how they come out.
Extract the socket from the assembly and simply pull the light bulb from the socket.
Insert the new bulb into the socket.
Turn the lights on and check to make sure the bulb is working properly.
Insert the socket back into the assembly and turn a quarter turn clockwise until locked into place.
Reinsert the plug fasteners in the liner. Push them into the predrilled holes and push down onto the plastic screw.
Remove the screwdrivers and close the trunk.