Wondering if anyone can help with info disc brake prop. valve.

I used one from a 70 Duster on Vixen, however, it did not have that adapter on the top. The line from the master cylinder screwed right into the top of the valve. The ONLY mod I had to do was go up one size on the fitting going to the rear brakes. All I had to do was cut the old fitting off, get the correct fitting, slide it on and reflair the line and screw it on. Other than that, the whole thing was a bolt on swap, dual reservoir disc brake master cylinder and all. I still have not swapped on the discs yet and it stops great. I would use the one from the Duster.