That's weird - I guess you can add fuel pump and fuel pressure regulator to the list of suspects.

Do you know what ECU number you have? - Never mind - I see you have a '91. I have a good spare 6477 for an '89 I was going to suggest sending to you to swap in and see if it would run, but it's different from the '90s and '91s.

Check all of the wires and harness connectors around the distributor and coil - maybe spray inside the connectors with some electrical contact cleaner (RadioShack) just to make sure they're ok. Have you checked the coil resistance? Primary resistance should be 0.72-0.88 ohms. Secondary resistance should be 14.5K-19.5K ohms.

When were your wires replaced? Check the coil wire resistance?

Check the mounting bolts/nuts where the upper plenum attaches to the lower intake. Don't over-tighten in the aluminum, but snug 'em to 14 ft.lbs to make certain you don't have an air leak there.

Still thinkin' - this one's a head scratcher (as you've found out).

Frank