My 1951 3800 has a similar Huck style brake system, infact, I'm almost certain our rear cylinders are the same. Check out my photobucket pictures on my gallery page to see for sure, or I can email you some photos of mine. I tried to hone my cylinders, but couldnt make them clean enough, so I bought new ones through classic chevy parts. The hardware is also available. They're pricey, but I think you are better off replacing them. Now my challenge is finding rebuild parts for the Bendix Hydravac unit. Good luck.
