You just need to get a retro-fitted HID kit that is for bulb code H7 (for headlights) and H11 (for the fog lights). No cutting is necessary as the HID kit you buy should be H7 to fit into the stock headlight casing socket. Good luck!
I installed the HID kit on my 5 (both low beams and fog lights) and it is simply wonderful. Since the low beams are "projector style", the result is at its best! The "straight line" that the normal lights do normally, is accentuated dramatically. If you live in Canada, though, you might end up with the same problem as me... The DRL (Daytime running lights) are plugged on low beam and HID DOES NOT LIKE DRL!
I ordered HID for a Mazda 3, my Mazda 5, a Ford Fusion and a Hyundai Accent. The guy is quick to send the kit and none of the HID kits was defective or stopped working. I know there is alot of HID shops on the net, but I know that this guy is good.