the first frame I built didn't have a brake bridge and I didn't have any problems. as long as you take you time you should have no problem moving it up a quarter inch. if it's brazed in you may be able to heat it up and knock it out. or you could cut it out and patiently grind out the remaining material and replace it with a new one. it would also be a good idea to put in a dummy axle while you're doing all this. fwiw, I use 1/2" X .035" 4130 tube for my bridges.