If your bike doesn't take recessed brake bolts, you should use the front brake in the rear and vice versa. You will still need to drill out the front. The front brake has a long enough bolt that it will come through the rear where you can attach the nut. The rear brake has a short bolt that you can reach by drilling the front.

The only problem with this scenario is that Campy brakes are different front and rear, or at least my Chorus brakes are. One is single pivot, the other dual. I don't remember which is which though.