I am writing in this old topic because many riders are faceing the light bulb problems. It is a real

to get your hand up in the light socket. So bite the bullet and remove the speaker housing, remove the four small screws (do not loose them, special screws) carefully holding the assembly, pull the speaker plug wire connections apart (DO NOT pull the wires to do this)
The original bulb for the headlamps are Phillips halogen 45 watt and tab specific, no other 9003 bulb will work without modification (removing the 2 lower tabs and keeping the top tab. I have not been able to locate the conversion ring.
You can still find the original Phillips halogen light bulb if you want or put a 9003 halogen with tabs removed, it will stll sit in the bulb socket and once clipped in be solid. OR come into the modern age and replace the Halogen bulb with Bright LED 50 watt 9003 bulbs. You do not need any fans atteched to cool them, they come with a heat sink built on them

and have the low and high beam on the bulb. I have been using OXILAM H4 9003 LED Headlight High/Low Beam 6000K Bulb Fit Motorcycle , 2 for less than 30 bucks. You still have to remove the lower tabs. Like all replacement bulbs, you may have make headlight adjustments. Don't put the speaker panel back untill you check for proper headlight projection. The high/low adjuster is the white wheel just above the socket. I recommend a flashlight or head light to do any of the work or a shop light, it's dark working in the tight areas.