When u said HID kit, I assumed it was an HID kit and some hardware. The link you are showing is a not a HID kit, but a complete headlamp, which is a much better start.
If they are made like the Hella 90mm, they might be switchable by turning rear end of projector unit.
If there is no such thing bulit in, then theoretically, u could flip the shield. But its not that easy in real life. Shield is usually very easy to screw off - mounted under three torx screws. Shield itself can have assymterical mount points, so that it is not mistakenly mounted the wrong way under production. Vertically, the shield is mounted with 0.2mm tolerances, so it would take some trial and error to get a flipped shield mounted rigth in 3 dimensions.
This is the assymetrical shield om the Hella 90mm:
I recommend you to get most expensive torx bit you can find, posibly in combination with some pozidrive type screwdrivers and open up the projector units!