http://www.mustangsteve.com/PropValveSide.JPG Clockwise from upper left...Rear bowl of master cylinder, front bowl of master cylinder, rear brake line to rear wheels, left (or right) front, right (or left) front. Hope that helps ::
If you get one from an 80's LTD II or something similar, it has all standard 3/16" flare fittings so you don't have to get the special fittings. I have no idea why Ford had to use different sizes, other than to make the assembly line "fool proof". If you are running lines near headers, be sure to install that steel spring-looking stuff on the lines (get at junk yard). It acts as a cooler for the steel line to draw heat away from the fluid.