I'm in the process of rewiring a lamp (which I have done before in the distant past). I'm now ready to attach the cord wire to the socket. It looks like there might be a screw missing? There is nothing else in the packaging. From the instructions, it looks like the brass and silver screws should be opposite. The only non-brass screw is 90 deg. from the brass. The pictures below are three 90 deg. rotations from the position of the brass screw.

I don't want to attach wires to the only two screws there and have the lamp go haywire when I plug it in! Thanks for your help.