Hy bowtiesr4me, I'm afraid I have questions also. First was the master for a disc/disc system or a disc/drum system? If it's for a disc/drum system it should already have a residual pressure valve built in to the rear system. As for the proportioning valve, you could use a stock one, or if you have to have something new you could just put a pressure reducing valve in the rear system, hope that helps.
