67 Barracuda Master cyl cap leaks

Some of the replacement master cylinder's main bodies are really rough on the top surface and won't seal up. I went through a couple of those cheap units then decided to get a new Raybestos Professional Grade from rockauto.com and that had a nice smooth surface and seals well. No more leaks. I found if that main body sealing surface is rough it won't seal up. And make sure the rubber seal is positioned correctly so it meets the body. I had to glue mine to the lid with Weatherstrip Adheasive to make sure it stayed positioned correctly.