Sheesh.
New coil, condenser, points, cleaned and gapped the plugs, rebuilt the carb, check timing . . . realized I'd forgotten the cam lube for the new points and took the distributor cap off to do so. Double checked timing and it was 180 degrees out! Pulled the distributor and the pin in the drive gear was shredding on the ends. I guess that's what the real trouble was.
Distributor is a Delco-Remy rebuild, just about a year old. They must have used a pretty soft metal in the pin.