Each end of the trim has bolted-on clips and the middles are snapped onto plastic clips, which are riveted to the body. As jor mentioned, you can get access to the nuts for the end clips. He mentioned removing the taillight for the back one. The front one is accessed by popping out a body plug at the front of the box (inside) on each side:
If you want to remove it the easy way though, simply get a thin piece of tin, maybe 1" wide by about 6" long and put a 90° bend on the end of it about a 1/8" wide. Then just carefully slide it up under the edge of the trim to release the clip. It''s very easy, and you don't have to worry about bending or denting the thin trim.
![Very Happy :D](./images/smilies/icon_biggrin.gif)
Doing it this way also makes reinstalling the trim a LOT easier. Of course, the clip will remain attached to the body, which shouldn't be a problem unless you're needing access to that little area for sanding/painting.