Ignition Coil Overheating

The 7.98 volts coil + running is a pretty good value. The 1 ohm ballast resistor when cold is a good value; make sure this was measured with the wires removed from one lead on the ballast. Run the car for 5 minutes, shut it down, quickly pull the wires off of one end of the ballast resistor, and very quickly measure the ballast resistance. It should be around 2 to 3 ohms hot after idling for a few minutes.

Measure the coil resistance cold; should be around 1.5 ohms.

Are you running an orange or silver ignition box?

Does the intake manifold have the exhaust manifold heat passage? If so, if the coil is mounted near the center of the intake on either side, then it can pick up heat from that passage.