Do it yourself, change the tail light assembly on your Ford Crown Victoria, the model made in the years 1999, 2000, 2001, 2002, 2003, 2004 and 2005. The replacement process will require an 11 mm socket wrench and about 20 minutes of your time.
This repair is fairly easy. You can start by opening the trunk of your car. Behind the tail light you need to replace, inside the trunk, you will find a plastic knob that you must remove, like the one in the image below. It can be twisted out by hand.
After you get rid of that retainer, you should be able to pull over the insulation, gaining access to the back of the tail light assembly. Here you must remove the three 11 mm nuts that hold the lens, similar to the ones you see in the next picture.
After you do it, you can simply pull out the lens. Behind it you will notice the electrical harness, that powers up the two light bulbs. Remove it by twisting the sockets of the bulbs counterclockwise. Service the bulbs if needed or make other desired repairs and then reinstall the lens into the body of the car. After you secure it with the nuts and cover it with the insulation, you should be ready to go. This is all you have to do, if you need to remove and replace by yourself the tail light assembly on Ford Crown Victoria, the model manufactured between the years 1999 and 2005.