The old master cylinders can be sleeved, and the cost is about $100. They can be done in both stainless steel or brass. My preference is brass. I have used Apple Hydraulics to sleeve many a cylinder. The 1962 master has a thumb screw for the top, and the 1963/64 has the bail wire to hold the top on. I was told, however, I have not seen one in person, that in 1962, there were two different master cylinders, one for power brakes, and one for manual brakes. The difference being in the lower part of the casting. The only ones that I have in my collection of junk parts all came from Corvairs, which in all outward appearances is the same as its big brother, the full size car. Even the rebuild kit is the same.