LED H4 Bulb FXST ('03-on) / FLSTSB Modification

Step 1: Due to the mount inside of your stock headlight
housing, our H4 bulb will not fit without modification.

Step 2: Remove bulb base from bulb as shown.

Step 3: The metal cooling fins on the bottom side of bulb need
to be ground down.

Step 4: As you grind cooling fins down, periodically dip only
the ground part into water to cool off.

Step 5: Grind cooling fins until they are flush with last fin on
each side as shown.