Abstract: A vehicle guidance system which monitors the path of a towed farm implement with respect to a track provided by a previously cut furrow and provides visual cues to the towing tractor operator to maintain the path of the towed implement parallel to the track of the previously cut furrow at a constant, predetermined distance regardless of the path of the tractor towing the implement. The guidance system includes an elongated metal sled runner which is mounted on a doubly articulated carriage device. The sled runner rides in a previously cut furrow and closes an appropriate microswitch if the towed implement veers from the desired path.