I'll try and be brief. Bought a restomod 67 with Kelsey Hayes front discs, no power. Car was a disappointment in the braking department. Called The Mustang Shop in Chandler and made an appointment to install a vacuum booster. Talking to the tech there he recommended a Wilwood front disc setup with a new mastercylinder (15/16ths bore) and no booster. He said the difference in forty year old technology and what is available today should be significant. During the installation he called to tell me the car didn't have a proportioning valve. He recommended a adjustable valve on the rear brake line. After all is said and done, I notice a marginal difference from before. . I'm at my wit's end . Anyone got a suggestion or two?