Robert Emhardt, who plays Mr. Foster, also played Malcolm Tucker, a businessman stranded in Mayberry by car trouble, in the 1963 episode, "Man in a Hurry." He drove the same Lincoln Continental in both episodes. Not correct- the second appearance he drives 1966 Lincoln
The crew shooting the commercial contained several members of the actual show's crew.
Although this may be Ronnie Schell's TV debut on The Andy Griffith Show in 1966, as the director of the television commercial featuring Aunt Bee, most people will recognize him from his recurring character on Gomer Pyle: USMC in which he played Gomer's pal Duke Slater beginning in 1964.
Mr. Foster says his address is 403 Elm Street in Raleigh. In fact, 403 Elm Street is a residential home in Raleigh near the corner of Oakwood Ave and Elm St. About a block from the Oakwood Cemetery.
In this episode, Andy says to Goober over the phone "you know I never drink." Yet, in season 3, episode 2 "Andy's Rich Girlfriend," Andy orders a draft beer when he takes Peggy out to eat at the fancy restaurant in Raleigh.