HOTTT!!! coil

I'm assuming this is a new issue.

I think for the price of a stock coil it would be the first thing I would swap out

You can measure the positive voltage between the battery negative and coil plus while it is running. It should be in the 6 to 8 volt range at idle and 8 to 10 at a few thousand RPM.

If you are getting full battery voltage to the coil positive, that can and will cook coils unless they are designed for full 12v.

Ballast resisters fail open so not likely the issue UNLESS it is bypassed or the coils that make the resister are somehow shorted in the back.