Do the HID lamps need to be modified to fit the Halogen headlight housings?
If you are doing a conversion for a 9006 setup using the custom fabricated beam pattern correct kit, then no modifications to the HID lamp is needed to make it fit. Some headlamp housings where the 9006 bulb is held in by a clip may require the removal of a small tab on the inner edge of where the bulb enters the housing. This can be done using a file, but care must be taken not to allow any particles or dust to enter the headlamp housing. For custom conversions other than 9006 using the standard unmodified conversion kit, modifications are required.