ecu box and coil

Search "ready-to-run" HEI distributor here. Only $45 for your engine (ebay). Works for many people here, but no go if you shun anything from China.

Before that, try grounding the ECU case, as suggested. Also, get an in-line spark tester (cheap at Harbor Freight). If you see spark flashes, try spraying starter fluid down the throat. As is, you are "flying blind" and just running down your starter and battery.