I recently upgraded my running lights to HID using the stock ballasts in my 02 GS. It only required minor fabricating. I took both Bulbs and dremelled the ridges so that about half of the ridge surrounding the plastic remained. Once you do this you can insert and twist into the fixture for a tight secure fit. They are level and are VERY secure. Sure beats making a fixture, as there aren't many options due to lack of room and places for securement in the GS! Hope this helps somebody out!