Your original engine harness plugs into the green and black plugs, and the gray plugs plug into your obd1 ecu. The lose wires are ran into your engine bay to the components that shown in the directions.


You need the mpfi harness to add addition injectors and a resister box to your car. This mpfi converted harness needs to be for a OBD0 setup car because you already bought a obd0-1 subharness (unless you like wasting money). That mpfi harness is a engine harness and you will replace your current engine harness with that and you will have to de-pin a few of your original ecu plugs. Then those plugs will plug into the obd0-1 subharness, and you're basically done. I would suggest you researching mpfi conversion and obd1 conversion for me info.