Just run the front 02 sensor, the one in the manifold not the catalytic converter. That is "Bank 1" and all OBD1 will look for. As far as plugs that won't plug up from the DX harness are the distributor plugs and injector plugs. So you will need to run an OBD1 b-series distributor and OBD1 injectors to use the DX harness. WHat OBD1 ecu are you running? your DX ecu won't work, so I'm assuming you found a pr4 obd1 LS ecu?