[ddsmith]

Try this out. The fire may have caused problems with the resistance wire that goes to the coil. That is of course if your still running points type distributor. I assume when you say it will start but will not stay running means that when the key is in the start position you hear it fire but when the key is returned to the run position it dies. If that is what you have, run a jumper wire from the positive battery terminal to the terminal that the yellow connects to on the coil. That will keep 12V applied constantly. If it runs fine then you need to replace the resistance wire that breaks out of the wire harness above the distributor and goes to the firewall junction block. The wire is pretty noticeable because it has a cloth type covering and connects to the yellow wire in the harness.
Sorry I didn't notice you were running HEI. You probably are not using a resistance wire in your setup.