The wheel cylinders for my '62 were really expensive. I bought a hone and rebuild kits for a fraction of the cost.
The stones on the hone just about covered the entire surface area of the cylinder, so I didn't worry about a hand held drill getting me an uneven bore. The flex hose would take up any misalignment, while the flat stones should keep themselves square in the bore.
Remember, you're dealing with aluminum pistons in there--aluminum corrodes, and aluminum oxide is very thick/furry, even though not much thickness is removed from the parent piece. That's probably why they're frozen.
For mine, I cleaned off the sides of the pistons with a very fine wire wheel in my bench grinder. For the face of the piston, I simply cleaned it off as well, and then layed it on the concrete floor, face down, and did nice even Figure 8s, cleaning off the face and making it relatively square. It's just fluid pushing against the face though, so I wasn't terribly concerned with a square face.
New seals, new bleaders, and attention to detail. Driven every single day for the last 6 months, a minimum of 25 miles to/from work every day (and 3/5 days a second round trip home for lunch), and I haven't had a single leaky cylinder or brake problem.
But I'm still saving for a dual reservoir/front disc kit!
-Brad
