Just took a look at the side light fixing on Aldermog (Summer 09 build):
The larger front and smaller rear bolts go up from under the wing into the light unit. The wire goes up through a third hole with a plastic sleve showing.
The light unit is well forward of the wing stay,there is a large "winged U" shaped plate bonded to the wing so that the stay bolts to that plate. There is a secondary wing stay further back near the little indicator repeator.
No way at all that the side light could move.
A great improvement on mine by the look of it. But then again yours is a tad younger!