If you have some Torx screwdriver bits then it's fairly easy to take the bumper off, then you can take the headlights out - each headlight is held in with 4 screws, the lower 2 being covered by the bumper.
If you have the factory HIDs then bumper removal is the only option, as the headlamp units are deeper and the covers are screwed on.
If you have the factory HIDs then bumper removal is the only option, as the headlamp units are deeper and the covers are screwed on.