Master Cylinder: 67-72 GM w/ Drum Front (NEW)Aftermark remake of the early DRUM DRUM front & rear. NOTE this has the single bolt type lid This has a deep hole in the master cylinder piston.. other suppliers may not tell you this but you need to be sure you have the same.. or have an extension on the pedal push rod or power booster If unsure.. you DON'T have to normally take off the master completely just unbolt from the booster . keep the lines in place.. don't touch them hopefully.. just unbolt