Pat,

I did my own master cylinder a few years back for my 68 Hemi Road Runner. The car had sat for some time and I had difficulties trying to get it apart. Finally ended up using some compressed air to get the piston out - made a mess so do it outside... I had a rebuild kit that I picked up at Carlisle and all the parts were perfect matches. I used one of those honing stone tools from NAPA that you put in a drill and the bore turned out very nice. One thing I did find once it was cleaned up (glass bead) was that there is a date code stamped on the front snout. Mine was within a week of the build date and knowing the rest of the car's history it was a safe assumption that it was original to the car. I sent the cover and hardware out to be re-plated and painted the MC, it still looks good today. I also used DOT 5 fluid so it will not screw up the paint on the MC or on the sheet metal.
Good luck with your project!

Jim