. . . "(1) After January 1, 1964, every motor vehicle, trailer, semitrailer, and pole trailer, and any other vehicle which is being drawn at the end of a combination of vehicles, shall be equipped with at least two tail lamps mounted on the rear, which, when lighted as required in RCW 46.37.020, shall emit a red light plainly visible from a distance of one thousand feet to the rear, except that passenger" . . .