Well, one you wont be able to razor blade them becuase they are like 1/4-1/3 inch thick hard plastic...I had to use a dremel
Theres actually "two" sections of the foglight holes...the larger outer one, then the small inner piece. These are seperated by a "vertical split" you should see. If you just cut the outside portion, you wont see much but if you cut the inside too, you will see a braket type thing.
I would say not to cut them unless you are doing somethin with them...like setting up an air induction system for the brakes or whatnot. Better to keep the FOD outside the car.