I use a dwell/tach meter to make sure my points are gapped properly. There is also a points resistance test that measures voltage drop across the points when ignition is on and the points are closed. The needle should barely move on the points test function. If the points are burnt, the needle will move higher. When you regap your points, your timing will change 1 degree for every degree of dwell change. I always get my dwell set to 37 degrees so I don't have to change the timing when I'm done replacing the points. I wish Ford would have the door in the cap so that the dwell could be changed with the engine running like the Buick my Dad had when I was young. Since they don't, I have to set them with the cap off, while turning the engine over, and set it so the needle of the dwell meter is bouncing from 35 to 39 degrees. Then retest it with the engine running.
Steve