I can't help much with the Gen I Solara but on the Gen II (2004 and later) all you have to do is push back the tab on the lens (frame) covering the bulb and lift the lens away. Then turn the bulb about a quarter turn to the left and pull out. Installing the new bulb is the reverse except the lens should simply snap into place. Gen I may be something similar or might require a screwdriver. Either way a close look should produce the answer.
BTW, on the Gen II there are two bulbs. Replace both at the same time if one is burned out. The replacement bulb number is shown in your owner's manual.
Cheers
how do you change the light bulb over the license plate on 2000 eclipse
How do I change the license plate bulb on a 1993 Lexus ES 300
sledghammer
how do you change the rear license plate light on a 1999 Buick Regal
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simply unscrew it
To change the license plate lamp on a 1998 Bravada, locate the bulb. Visit an auto parts store to obtain the exact bulb and screw it in place.
To change the license plate light on a 1998 Chevy Cavalier, reach up under the bumper and remove the bulb over the license plate. Then put a new bulb in the socket. The bulb can also be accessed by removing the lens on the outside, but there are screws to remove first.
A Chevy Tahoe's license plate bulb can be used to light up the license plate. In the dark the license's plate will still be visible.
The 2006 Legacy license plate bulb is accessed by removing the liner in the trunk and un screwing the plastic socket.
same way you do
Changing the license plate bulb on a 2002 Lincoln LS is quite simple. You must first remove the license plate first. Then unscrew the old bulbs and screw in your new ones.