Yes you need ballast. That's a problem, but May not be your only Problem. When you re-wired, you eliminated the factory resistor wire which provided the proper key switched voltage to the coil. Now you're feeding it full voltage which the points do not like, and thus the coil overheats out of sympathy for the points being mistreated. For a v8 engine, you should shoot for a total primary resistance in the range of 3.0 to 3.4 ohms, with a midpoint being ideal. That means taking a measurement across the +/- coil terminals with all wires discon, to establish the primary resistance of the coil. Subtract that amount from the target value to determine the amount of ballast resistance needed to satisfy the difference. For example, let's say your coil shows @ 1.4 ohms resistance when measured across the terminals. 3.2 minus 1.4 equals 1.8. You'd need a roughly 1.8 ohm ballast resistor to achieve a happy total in that example. But measure your coil. Don't guess. Also, you will need to run a wire from the solenoid 'r' terminal and hook it either to the coil side of your ballast resistor, or run it directly to the coil + terminal. This is a resistor bypass to feed full voltage to the coil and points only during starter cranking. Once the engine catches and the starter releases, the resisted feed takes over.
*** also, if you've left the ignition in on position without the engine running for longer than a few brief moments, you better pop the cap and look at your points. They might look like hefty smurf has smurfed his dna on them as a result. This situation should be avoided no matter what ignition system you have. Use acc to power your sound system when the engine is stopped. The on postion should only be used while the engine is running, and very briefly when stopped to perform quick diagnostic checks. Pick up a new set of points if yours show any discoloration from overheating.
