Head lamps arranged to provide a single distribution of light not supplemented by auxiliary driving lamps shall be permitted on motor vehicles manufactured and sold prior to April 29, 1939 in lieu of multiple-beam road-lighting equipment herein specified, if the single distribution of light complies with the following requirements and limitations:

(1) The head lamps shall be so aimed that when the vehicle is not loaded none of the high-intensity portion of the light shall at a distance of twenty-five feet ahead project higher than a level of five inches below the level of the center of the lamp from which it comes and in no case higher than forty-two inches above the level on which the vehicle stands at a distance of seventy-five feet ahead; and

(2) The intensity shall be sufficient to reveal persons and vehicles at a distance of at least two hundred feet.