In 1968, Plymouth circulated this line drawing to highlight the Road Runner’s long list of standard features. One odd detail separating ’68s from ’69s was the color of the “beep beep” horn. First-year cars got a basic black horn (with special aluminum windings to emulate the cartoon bird’s call), while second-year cars (and all Road Runners through ’75) came with their horn housings painted light purple. A sticker reading “voice of the Road Runner” was affixed in ’69 and beyond. In ’68, the hood scoops were non-functional, not even on Hemi cars.