It sounds like you have a short somewhere in the fuel pump circuit. Hate to say it, but the best thing to do would be to get out a multimeter or test light and continuity tester and a wiring diagram and start troubleshooting. I would've guessed the relay was shorted out, but since you've replaced that, it might be harder to find. The yellow wire from the battery goes two places: to the fuel pump relay and the constant power for the EEC, so I'd check that out first for any shorts to ground, as that is very possibly the link between a hot(temp.) power wire and no power to the EEC (which would mean no spark).