3rd Eye Brake Light Questions.

 I have a 1995 Corsica and need some good suggestions to fix or clean a rusted socket. (If cleaning is suggested do I undo the battery post to avoid being shocked?) Also to get to the socket do I unscrew the 2 screws at the sides of the 3rd Eye Housing Assembly? The last time I done this the whole assembly went into several pieces and I liked of never got it back together. Hope there is a better way to get to the socket and bulb.
 
                                   Thanks in advance,
                                        Rustybolt.