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What coil are you using? Internal or external resistor?
Check the actual voltage going into the coil when the engine is running. The coil should get warm but not hot.
Post the voltage.
Remove the high tension lead from the coil to the dist, hold it near a good ground, crank, what do you get?
Do you have a ohm meter to check the points? With the points open, ignition on, bridge the points with a screwdriver, do you get a small spark?
Did you check the voltage to the coil + terminal?
The coil could be bad now. The coil takes the 12 volts and increases it to 25,000+ volts. When it steps up the voltage it creates heat, so coils can get hot. If the key is left on with the points closed you will not only kill the battery but can also ruin the coil. If other components in the ignition system are substandard or not working correctly then the coil can't release the voltage and overheats.
As for your problem you need to make sure the voltage is not over 12 volts. If the voltage regulator is bad and putting out too much voltage the coil will go bad. So that's why I need the voltage going to the coil both at rest and while running.
If you hold the high tension wire, the fat one from the center of the coil to the distributor next to ground do you get spark?
So the problem is the distributor. Check for clean terminals in the distributor cap. Are your spark plugs clean, not black and no build up of carbon. Check the surfaces of the points, are they smooth or pitted? If pitted use a fine file or sandpaper to clean them. If transfer of metal, then replace the condenser.
Your coil should be fine, it is firing.
If you have spark, the ignition is working. Have you checked the timing? Spray a little starting fluid down the carb, what happens?
If you have spark at the coil or spark plug it should work. Try this, take a new length of wire and run it to the + on the coil directly to the battery. Crank the engine, what is the result?