From the pasture; The valiant story of my '66 Valiant

Great find !
I love it !
Oh btw I plugged one port on the brake block that splits the front left right rear lines a made a new line from the front port ( closest to the firewall) to the original brake block. I then coupled the new rear line from the proportioning valve to the rear system.

If you want to make that slant 6 wake up at freeway speeds change the entire exhaust system to 2 1/4” but you’ll need a muffler that gives it just a bit of back pressure.