I am changing the door handle on my LX. When I pulled the interior door panel off, I noticed a piece of plastic covering the door. It looks like it keeps water from getting on the panel. Obviously I have to pull it off to get to the handle. My question is do I put it back on when I am finished? It looks like it is not reusable. Do I have to put that insulation in too? That stuff was falling all over me when I was under the door getting the plastic screws out. Also, do I drill the rivets out from the outside or inside? One other question. My door lock is not working. Does anyone have any input on what could be wrong? The actuator works, the lock won't go down. It must be bent or something. Thought I would fix this while I have it apart. Thanks for the help.