For those of you who had to install your own front license plate bracket, here's a rather elementary question, but I'm a bit nervous about drilling holes into my Prius... Reading the pre-delivery service instructions, it seems to indicate that you are supposed to mark and drill holes into the bumper where the bolts that attach the license plate to the bracket might come into contact with the car (holes B). Then, you use the self-tapping screws to mount the bracket to the bumper (holes A, which are indicated by dimples in the bumper). So this would result in a total of 4 holes in the bumper. Is this right? Is it really necessary to mark and drill the first set of holes (holes B)? Ack. Do not like the idea of drilling into my Prius.