Automatic overhead garage door installation

Has anyone had luck installing the entry sensor on an overhead garage door? I'm having trouble installing the sensor close enough to the door to work, but not so close that the moving mechanical bits knock into the sensor. If I don't hear any other solutions I may make a 90 degree mount that attaches to the rail and sticks over the door so the sensor can be closer. I figure the cars side mirrors will ensure that the sensor will have plenty of room to reach out over the door with no risk of hitting the car.

I tried mounting it on the side of the door, but that's where the metal cable runs... and since the cable is metal the magnet seemed to like that better than the door and stuck with it instead :)

Thanks in advance