He only appears briefly, but John Stephenson was cast as General George Armstrong Custer in a season 1 episode of F-Troop.
In "Old Ironpants", Captain Wilton Parmenter (Ken Berry) is transferred to another base for a 2-week course on military techniques. When he returns to Fort Courage, it just happens that he's in the company of General Custer.
2 years later, ABC tried out a hour-long dramatic series based on the life of Custer, with Wayne Maunder in the title role, produced by 20th Century Fox. It lasted one season. I think you can see just how versatile Stephenson was in this episode, even though it was just for a short time.