How to change my signal light on the taillight?

I have a 2002 buick LeSabre and I need to replace both the brake and signal light on the left taillight. How do I get the taillight cover off so that I can do this? Or is there another way I'm supposed to do this? Thanks in advance for your anwers!How to change my signal light on the taillight?In your truck, pull the mat up on ths side. You will see the back of your light. You will see a plug type cap. Screw this to the left and half turn. This will unlock and you can pull the entire fixture out. Replace bulb----replace fixture, with a half turn to the right until you hear it snap ( locks). Tuck your mat back into place and your good.How to change my signal light on the taillight?do it from inside the trunk. it's quite easy.