Just found out some interesting info today. There is a reason why there is no manual brake master cylinder option listed for a '71 1/2 ton. Although there are 2 styles of master cylinders they are both 100% interchangeable. So long as the part is for a 1/2 ton pickup it will work just fine with either manual or power brakes. So, I went through all the hassle of running around for the "right" master cylinder when I had the right one from the start. Well, now I know and I had to let everyone else know too.
