If the key was on and the points are closed, it would supply current to the coil overheating it and burning it out. I can attest to this as it happened to me while I was rewiring and testing circuits.
On another note, your coil and ballast resister should not be close together because they both generate heat. Most resisters are mounted on the firewall.
Last edited by Phak1; 12/14/2025 1:49 PM. Reason: Added info