Looking at information that I can find it appears that the 1990's vintage Chevy 3500 used a 1.250 bore master cylinder so that is what I will plan to use. Once I source the master and proportioning valve (adjustable) I will tackle the replumbing of the brake lines to make it all fit and then work on getting the adjustable proportioning valve dialed in.
I noted that Fibonachu used a 4 port adjustable valve but I think a 2 port valve would work for my system. Any insight regarding the benefit of 4 over 2 port valves before I pull the trigger would be appreciated.
