Packing List: 1x Engine Wiring Harness 7.3L Diesel, Including engine and transmission sensor connectors. Condition: New Compatible with: 1999 Ford Super Duty F250 7.3L Diesel Automatic Transmission Engine Wiring Harness 1999 Ford Super Duty F350 7.3L Diesel Automatic Transmission Engine Wiring Harness 1999 Ford Super Duty F450 7.3L Diesel Automatic Transmission Engine Wiring Harness 1999 Ford Super Duty F550 7.3L Diesel Automatic Transmission Engine Wiring Harness Precise Fit Part Numbers: F81Z-12B637-BA, F81Z12B637BA How To Install/Repair Wiring Harness? Step 1:Labelling the wires connections using the masking tapes. This step will help you make the installation very quickly, significantly if the wires’ colors are faded away. Step 2:Disconnect and remove the car battery from the vehicle using a socket wrench. Step 3:Disconnect the primary connection of the engine body wire harness. Step 4:Take a jack, jack up the vehicle, and disconnected all the wires from under the car. Step 5:Install the new engine wiring harness. While installing new wiring, ensure that the wires route away from the hot exhaust pipes and other engine parts. Once you are done, reconnect the battery to the vehicle, and you are good to go. If you are not sure this item will fit your vehicle, please email us your car photo or provide your vehicle's YEAR, MAKE, MODEL and ENGINE SIZE before you purchase this item.