Bigmike, Are you going to keep the original drum brakes or go to disks in front. If you are keeping the orig drums, no need for a prop. valve you can get a master for a 69 mustang (drums front & rear). That's what I have done on my 46 it works great. You'll have to fab a mounting bracket but it's an easy job.
If you would like to see a couple of pictures I can email them to you. (sorry unable to post here)
George
