A stereo imaging device on a propelled portion of the receiving vehicle collects image data. A container identification module identifies a container perimeter of a storage portion in the collected image data. A spout identification module is adapted to identify a spout of the harvesting vehicle in the collected image data. An alignment module is adapted to determine the relative position of the spout and the container perimeter and to generate command data to the propelled portion to steer the storage portion in cooperative alignment such that the spout is aligned within a central zone or target zone of the container perimeter. A steering controller is associated with a steering system of the propelled portion for steering the receiving vehicle in accordance with the cooperative alignment.