I slipped some expandable sleeving over the bundle of wires going to the front of the car and secured the harness to the firewall to the left of the load cell.
The harness routes under the upper chassis tube and is secured to the outside.
The harness will split at the top of the radiator and route to the various loads at the front of the car: lights, fan, and horn. I went ahead and installed the horns along the upper tubing beside the radiator.