I had to remove my rear lights just the other week to swap some bulbs around ...
You'll need a small flat screwdriver to remove the plastic covers on the lights, then a 10mm socket to remove the 3 bolts for the lights.
Once you've got those out, it's simply a case of pulling the light away from the car .. there are 2 clips which also hold the light to the car, but these shouldn't be any problem ..