Were not talking about an old bike here, so drilling, especially as the frame/fork is carbon fiber is a really bad idea; any road bike from the mid 90's on has the same standards as a 2013 bike, with the exception of electrical fitting, and direct mount brakes.

For the 6700 brakes is the set is new as in retail boxed? (taking it as it is) If so, you should have at several bolts included for fitting them to different forks, if longer ones are needed, take the part number from the tech docs, and order them from a good LBS http://techdocs.shimano.com/media/te...9830753782.pdf

If you are having lots of issues, would be looking at getting the whole bike setup at a good LBS, as they can get the whole setup correct, saving you $820 groupset.