I caught the last half hour last week. In the last several minutes, he is shown with scale model freight hopper cars behind him. At least one historical still shot shows him hanging on a caboose. I am mostly unfamiliar with his discography and most of his songe except for Merle Haggard tunes which the Grateful Dead covered like "Mamma Tried" which starts out speaking of wanting to ride a train. I intend to watch the whole show when the opportunity presents itself. Here is the synopsis of the show. You can access and watch the FULL FILM.