Master cylinder/booster on 440 Duster

Machine man has a good point. I have a 440 in a 69 Dart and used an Eci kit which uses just a manual master cyclinder . The front are disc brakes and rear are 11 1/4" drum brakes which work fine . One thing I would change is the master cylinder to a Dakota style master that utilize a plastic reservoir with thread on caps ( no dripping or leakage from lid) .