Exactly, I have been saying this for a while. The bulb has to match the reflector housing.You can have all the lumens you want, but if the LED is not in the same exact spot as the filiment is on the Halogen bulb, you will not be happy with an LED. The motorcycle community has been dealing with this for years. The reflector is made for the Halogen bulb. A lot of the cheap LED companys do not put the LEDs in the same spot so the light is not reflected properley. I am not into LED headlight bulbs, and am not knocking them. They are great if made properly. So, if someone had found one that works, I would stick with that company. If not, you are risking not being happy with the results and throwing good gas money out the window! If you can afford to experiment, then go for it!!
Get to work!I really need to get a 3D printer so I can develop some of my ideas. LED reflector/lens is one of them. Something that would slide into your standard headlight lens. I wouldn't have to re-invent anything, just use what some cars already have.