4 wheel disc on 74 Duster - Prop valve?

The pics didn't really come out. It's like there's no way to get a phone or camera in there to get a good picture.
I'll try to describe it as best I can, but all I did was unbolt the rear brake line from the stock proportioning valve, screw it into the adjustable valve and ran a new loop of brake line between the proportioning and the adjustable valve with enough line to loop up where I can adjust it from the engine bay....
Pain in the but to bleed, but it works...

the same set up I used on my 73 dart sport with the 8.8 rearend swap. once it's bled out, it works really well. I did make some new lines from master cyl to the wildwood valve. I also had to make some ext. lines to hook to the oem lines. I also went to the hardware store and got a couple chrome 1/2" spacers for the prop valve mounting. Spaces it out from the inner fender a little.
I also back bled my rear brake system, it seemed to help, I work alone a lot.