Do it yourself, change the tail light assembly on your Pontiac Grand Am, manufactured between 1999 and 2006. You will not require tools for this particular repair, just about 15 minutes and a new tail light assembly.
In the beginning, you just have to open the trunk and locate the thumb screw behind the tail light you need to replace, as seen in the picture below. You should be able to remove it quite easily.
After you do it, try to move the insulation away, because this will give you access to other four plastic screws, that hold the tail light assembly, as you can see in the image below.
After you remove these four screws, you can simply detach the tail light assembly. Behind it, you will have to unplug the electrical harnesses indicated in the next picture, that powers up the bulbs.
Now you can simply replace the old assembly with a new one. If you need to service the bulbs, you have to take off the big plastic plate behind the tail light, where the bulbs are installed. After you finish all the repairs, you have to connect back the electrical harness onto the new assembly, insert it in its place into the car’s body and secure it with the thumb screws. In the end, place back the insulation in the trunk and you’re ready to go. This is all you have to do, if you need to change the tail light assembly on your Pontiac Grand AM, made between the years 1999 and 2006.