It's a little bit of a trick, but the best way I have found to do it is, center punch the head of the bolt, then drill a 3/8 hole through a 2x4. I say 3/8 because it will be easier to get out. Then stick the bolt in the hole and smack it in a few licks with a hammer and recess the head into the wood. Then throw it all up on a drill press and have at it. The bolt head being recessed in the hole will keep the bolt from spinning.
