third brake light question

Hi, today when i was watching my dad back up my 96 sl2 into the garage i notice that my third brake ligh (the one on the top) the center part is not working so i tryed to see how i could take it out and i couldn't figure it out so i was hoping i could get some help on it. and where i could get a light for up there if like autozone doesn't have it.

it has metal clips that hold it on. pry it off or you can yank on it, but dont go crazy or you will probably break the plastic. if autozone doesnt have it, which i doubt that, then advance, napa, wal mart, practically any place should have it. just hope its stocked and not out