It is lawful for any motorist driving a vehicle upon the streets of the city to make a right turn on a stop light signal, providing that the vehicle has first been brought to a full stop, and, provided further, that such turn can be made without interference with traffic which is proceeding through the intersection on a go signal, and, provided further, that a plainly legible sign shall be placed at such intersection which shall indicate permission to make such right turn, such sign to be in accordance with the requirements of the statutes and regulations of the state. (Ord. 269 § 1, 1966)