I just changed out my low beam bulbs on my M3 sedan from the stock one's (H7) to the (H7SU) MADE BY SLYVANIA. FOLLOWED VERG's advice and used a mirrow to see how every thing looked before removing any thing. After removing the electrical and rubber boot one can see just how the wire clip holds the bulb in. Push down on the clip and it will release from a tab that that is mounted on the bulb housing with a phillips screw. The screws do not have to be mover or loosened in any way.(2007 mazda3). Once the wire clip is loose just pull up on it and it will rotate out of the way of taking the old bulb out. The housing that holds the bulb in has an area with knoches that stick out and will accomidate the flat side on the new bulb and the adapter that you must take off of the old bulb and reinstall on the new bulb before installing. Seat the square area on the bulb and adapter between the raised notches on the housing. Once seated rotate the wire clip down and seat wire tab on the wire clip behind the tab on the housing held in place by the phillip screw. This is the most difficult part because of the small area to work in.I changed my drivdrs side in about 10 mins and the passengers side took me about 1.2 hrs.Just a matter of getting the wire clip hooked behind the tab on the housing. Lights shined whiter but I couldn't make out much difference in the downroad distance. Anyway I'm DONE.