kerry,
here is an article i found

http://www.mpbrakes.com/uploads/documents/mcplumbingpdf.pdf

i just tried laying under my 57 and see how i plumbed it, but my truck is too low and need to jack it up to see. LOL.
and mine has a factory style prop valve, and im running front discs, so not sure if mine would be the same as yours anyway.

hope this article helps.

leonard

1957 Chevy 3100 1/2-Ton
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