lost the fire

"No spark" is fairly easy to trouble-shoot. Connect an in-line spark tester ($4) from coil output to gnd or try the old "hold coil lead 1/8" from metal approach. Disconnect wires on coil- and install a wire. With +12V on coil+, connect coil- to gnd briefly and remove. You should see a spark. If not, verify that coil+ when the wire is grounded is 7 V or more. If not, suspect the ballast or the coil. If spark is good, reconnedt the ECU. It's only job is to short coil- to gnd as you did (and sense the mag teeth). Maybe try that from its connector. I think the ECU case must be grounded. Longer-term, consider replacing the Mopar box w/ an HEI module and losing the ballast. In your current setup, the 2 pin ballast is fine as long as you use a later 4-pin ECU or a 5-pin where the 5th pin is a fake (goes nowhere, test with multimeter).