Most of the old masters will give a full pedal after a rebuild, then drain down due to the corrosion compromising the bore. Once the pedal hits the floor, you're on your own. 1950 style Huck brakes have more parts that should be carefully and sparingly anti-seized IMO. Most every old line I've broken apart was paper thin due to internal corrosion. They can look like new on the outside, look inside it's another story!
