Indeed, Buster was fully intended to exist in place of Spike for the comic book series, until the release of the Fortress Maximus toy in 1987, which included Spike as a Headmaster partner, hence necessitating the hurried introduction of Spike into the comic book continuity. Returning home from college to discover that his father's garage had been destroyed, Spike investigated the Autobots' deserted base at Mount Saint Hillary, learning that Buster had been captured by the Earth-based Decepticons.
Spike
Buster