I just got in a new Colt ambidextrious safety for my LE6920. It came with a small allen head bolt with thread lock on it. It's not the small screw that holds the two pieces of the selector switch together, that screw is already installed and much smaller. I have no idea what this bolt/screw is for. I know how to install a selector switch but I'm holding off until I get this figured out. Help please.