The end credits differ from the norm. Rather than all the credits appearing over still shots of rural life, the credits roll over a moving aerial shot of a farm before reverting back to the standard stills.
The title is based on the old expression, "don't look a gift horse in the mouth."
In a running gag, Lisa says Oliver is 68 years older than her. Then she raises it to 72 years, and finally 81 years.
The Duke of Edinburgh that Lisa claims to have tripped would have been Prince Philip, husband to Queen Elizabeth II of England. He was made Duke of Edinburgh on 20 November 1947, which was the day he married Elizabeth.
The music in the tractor comes from an 8-track tape player, which was developed in 1964 and became a very popular mode of entertainment in automobiles and even in vehicles such as Mr. Ziffel's tractor.