There are 2 ways:
You can change projector lens made for HID or LED. (Moritomo -excellent brand)
Check theretrofitsource web page and go to /projector-kits/hid-led-projectors
Or to buy the complete headlamp but they are expensive..
Please let me know about because I swap from halogen to HID but feel brightness is not good enough for me. From a scale 1-10, mine could around 7.5. Now it is better than halogen bulb but goes little short.