[Noob Qu] On taillight teh 94-99

Sorry for Noob qu,
Does anybody know how to take out the nut all the way on the left or all the way on the right of the tail lights, it seems like i'm gonna break the white plastic thing.. which sits ontop of the nut. Please help thanks :)
I was assuming maybe its glued or or maybe stuck on by twisting or something but i'm unsure, i'd rather ask before i break and regret. thanks

edit: 1999 integra
the white plastic thing looks like it has wires coming out of it and its kinda squarish