Son of a...
I just picked up a new set of brakes for my Fuji (nothing special - no-name 39-45mm dual pivots). After messing with threading new brake cables, swapping on new derailers, and drilling out the mounts for recessed nuts, I find that the rear brake is too short. Bastards. So now I have to take my handy dandy circular file, hog out the bottom 2-3mm and pray that it's long enough. bah.