Hi Hemi 426 The drumbrake master cilinder has a smal valve in the output line to keep a little bit of presure on the lines all the time for disk brakes there is no valve like this I did the conversion on my 57 and pics will be afailable within a month or two I took a master cilinder from a dodge w200 the bore of the master cilinder must be the same as the original one for more details please mail private remco 57 4dr ht Daily driver