Won't Start need advice, Please read....

In addition to the above, did you ever properly set timing? Did you just set the idle screw, or did you actually adjust it? That is, for best / highest speed / highest vacuum

Maybe you have a dead cylinder or even a bad plug. One way to check this out is to "rig" a grounded probe, and pull the dist. boots up away. Sometimes, if you don't have a nice tiny probe, you can slip a small brad down beside each plug wire. Then, with the engine idling, go around the cap grounding one plug at a time. Listen to the engine and get a tach on it if possible (Dwell tach meter) Each cylinder should drop RPM about the same.

Does it idle smooth? Any reason to suspect a vacuum leak? You have a power booster?