USE A GROMMET.
Either push the wire through an existing grommet or drill a hole for a new rubber or plastic grommet. If the wires are in contact with bare metal, they WILL wear the insulation off & create a short which at best will short out your switch & lights, or at worst will catch your truck on fire.
By the E-brake cable, hood release cable, steering column, somewhere you'll find enough room to squeeze a small trigger wire through.