Have you checked the neutral safety switch? This is the switch the does not allow you to start the car unless it is in neutral or park. Mine went out I could not start the car but the electricals all worked. I could over-ride the switch by grounding out one of the ignition wires or relays under the drivers side dash. The switch is on the drivers-side of the ZF and has a connector that goes over the top of the transmittion and connects up to the harness. (Note: if you over-ride this switch you can start the rig in any gear.) Hope this might be of help and not send you in the wrong direction, just sounds familiar.
JK
JK