You likely have the 062 distributor which is the one used with the CD ignition unit. This distributor tends to wear out in two places - the top bushing on the main shaft and the cam lobe shaft. In the later case the wear seems to be from lack of lubrication.
Normally whenever you change the points you would put a few drops of oil under the rotor on the felt wick. This would be enough to keep everything free and moving smoothly. In the case of the 062 the points wear very slowly and can last for years. Since nothing seems to ever go wrong there's usually little or no maintanance performed. The cam lobe shaft shaft runs dry and can even sieze up or be full of rust. If it's still free there's a good chance that the main shaft is worn. I have a few tricks to tighten this area back up but if it's really worn I can only make it take some wear. The top bushing is fairly easy to replace but it helps to have the special tools to do this type of work.
The only really acurate way to set up a distributor is with a tester that spins the distributor while I check for start of advance, rate of advance, dwell angle and point of fire. Several different tests can be done such as testing the vacuum cell and point plate wear. This machine will also test the points and condensor.