Not sure why the ignition, harness etc. was changed unless it was from a later model. Is the harness OEM or aftermarket? Do you have the service manual with the wiring diagrams and, if so, have you checked all connections against that diagram? Could be a compatibility issue between the new harness and the ECM? Get to basics; fire and fuel are the two necessary elements required; do you have spark at the plugs? Is the fuel system providing fuel? I am suspecting that you don't have either one but let's start there.
With all the electrical components that have been changed, you are lucky there is only one code thrown.