I upgraded my '67 4 drum (power) coupe to front disc with a kit from Master Power Brakes. I do not remember anything in the instructions about lines being too short.
However, 1) the kit came with new lines for the front. And 2) I did run into one issue with the single rear pipe not wanting to reach the new prop valve because of the new valve having different positions where the lines exited. So I ended up getting a brake line "union" for one flare end to another and extended the line with a short piece of pipe from the local auto parts store.
Works great.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI
