As Roffle says, you send yours to them, they mod them, you re-install them.
To remove you need to take off the bumper. DIY
here. Can't recall if it two or four bolts that hold on the headlights, but it s/b obvious. Make sure you make several benchmarks (draw an outline with a marker) so that you can reinstall in
exactly the same place. The headlights have a lot of play, and if you don't follow this step it's going to be PITA to get them back in the same position.