Do it yourself, change the license plate light assembly on your GMC Sierra, the car model made in 2002. This repair is very simple and it will not require tools to do it, just a new assembly from your local hardware store. The replacement can be done in a couple of minutes.
Now, if you just look to change your light bulb, you can reach beneath the rear bumper, behind the license plate light assembly and twist the connector counterclockwise. The bulb then pulls out of its socket and can be serviced (see picture below).
After you pull out the light bulb, you can work to remove the assembly. You just have to push it to the exterior, or use a flat blade screwdriver on its retaining clip (see next image).
After you do it, you can install the replacement. The new assembly has to be hooked from behind, first and then just pressed slightly into the bumper. At the end reconnect the light bulb and you are ready to go. These are the steps you need to follow, if you plan to remove and replace by yourself the license plate light assembly on GMC Sierra, the model manufactured in the year 2002.