I would NOT drill. Maybe just superstitious but I have lived (barely) through a fork crown failure. And braking power is way overrated. Power enough to take you over the handlebars is plenty. A modern aero brake lever like Tektro will give you that with your Diacomps using Koolstops and good cables and housings. I am using very close to that combo on two bikes currently. Both have more than enough power. (I "detuned" one of my two dual pivot bikes with V-brake levers. Better stopping by a lot after I did that since locking up is so much less likely. I will probably do the same with my best bike or replace the Shimano dual pivots with SunTour Superbe if I run across a pair.
Drilling may be perfectly safe. But the consequences of a failure there can be very high. The failure I saw caused a 5 day coma and cost me seven years of my life.
Ben