Still more bits of artwork from the Disney booklet of 1977 (copyright WDP)...
These visuals show the usual storyboard-to-pencil-animation-to-full-color progression. I don't know who created the animation drawings, but the board panels on the left are the work of Disney veteran Vance Gerry, one of the old (and relatively unsung) masters who was at Disney Feature Animation from the 1950s until his death.
The last several years of Vance's tenure, when he was in his late sixties and seventies, Vance worked at the studio one day a week. (He had a company called "The Weatherbird Press" that kept him busy the rest of the time.)
But one day of Gerry artwork was fine with the studio. As another tyro artist told me years back: "Vance comes in here on Wednesdays and does more in one day than most of us do in a week."