Early 70's brake conversion HOSES.

If you are talking about fitting the hose into the metal flap with the U-clip, can you not spend a coupla minutes with a file to re-notch the "flap/D".?
I had debated that but really think it would be a PITA. My likely remedy at this point was going to be to grind a flat on the line end of the new hoses. If I F that up I can buy new lines. I could also have ends put on these lines. The issue there is time as there will likely be a long delay getting the factory ends.