The screw will go in on it's own. Mine looked the same but the screw went in fine. However, the sensor has a bit of an interference problem that tends to make it twist and not line up properly. Hold the sensor out a little bit as you get the screw started and you should be fine.
Edit: It is tapping itself in though, you will have resistance as you tighten it down.
Last edited by n3elz; 04-17-2005 at 11:30 AM.