I can't remember the sizes, but you'll need one small enough for pilot holes for the scuff plate screws (a good way to determine that is to hold up a drill bit to the screw and find a bit that is just a tad thinner than the main part of the screw itself, not including the threads). A couple of sizes ranging from about 1/8" up to about 1/4" and possibly a 1/2" or larger for the pins to easily fit through. It's much easier to make a small pilot hole and then use larger its to make the hole bigger rather than trying to get the large bit to make the large hole the first time. Larger bits with no pilot holes can easily "walk" (scoot off to one side rather than drill into the metal) across the metal and that won't be good at all! A thin round file will help quite a bit when/if you need to adjust part of the hole to aid in the pin going through the hood without rubbing. Don't be afraid to make the hole bigger if need be. Take the scuff plate and see how much area it covers around the pin. As long as you have enough room for the scuff plate screws to grab, you'll be fine.