Sickboy49 to go a bit farther with the distributor reclocking: with points the base timing can be set accurately with the engine off. My preferred method.
First rotate the engine until the damper pointer is pointing to your desired base timing mark. This will be to the left of the TDC point looking down at it from the front. (be sure it's the compression cycle of #1). Once you have the body of the distributor near where you want it, take a 12v test light and attach the clip to ground. Turn the key on to put power to the ignition. Put the testlight probe on the negative coil post. If the test light is off, the points are closed. Now slowly rotate the distributor in the opposite direction of rotor rotation. (Example, the big6 rotates clockwise, so would move the distributor body ccw.) The moment the test light comes on, stop. That is the point of ignition. Lock the dist. down there. Now verify which cap tower the rotor is pointing to, that's now #1.
This static setting will be within a degree of where you had the damper lined up when you look at it with a timing light running. If the T light shows it more advanced than where you set it static, then the centrifugal system is suspect.
