there isn't a whole lot of harness that hooks up to the dash. You have the VSS, a ing+ wire for the ecm, the aldl, the SES light, the wires to the brake swith for the TCC, and to the Nuetral safety switch. I would do like these guys have said, take out the RH inner fender, the RH kick panel and the glove box. Remove the ECM and pull the harness from under the hood. The headlight harness runs out of the DS. There may be a wire that runs to the A/C compressor, or spliced in. And you may or may not of had a IDLE up soleniod on the carb controlled by the ECM. Just split the harness apart and don't cut the heater wires you need.