I like the idea but I'm not following your plumbing. Your running the solenoid between the MC and pressure switch port? are the two lines out (FO & FO) going to opposite sides of the front brakes? I don't see a line to the (RO) rear out?
Mike, the picture you saw there was during mockup. Not everything in place....I have the stainless line coming off the master to a 90° AN fitting into the solenoid inlet. Then, the outlet side of the solenoid is tied directly into the "pressure switch port" of the proportioning valve. All the ports for the front lines are connected in the proportioning valve, so I decided to place the solenoid there, since it already had an 1/8" NPT outlet and the "pressure switch port" was also an 1/8" NPT. So, since I don't actually need the pressure switch, I put a brass block-off fitting in the original "front inlet" port. The rear is simply in and out as it was intended. I took a couple of pictures of how the setup is currently on the car and functioning.
Top left port- blocked off
Top right port- rear inlet directly from master
Left "center" port- inlet from solenoid outlet and master
Bottom left port- outlet to right front brake
Bottom "center" port- outlet to left front brake
Bottom right port- outlet to rear brakes