Factual error: Graham repeatedly sings a song he says his grandmother taught him: "Rufus Rastus Johnson Brown, What You Gonna Do When the Rent Come Round?" This was a Vaudeville stage composition written by Andrew B. Sterling and Harry Von Tilzer - in 1905. High Chaparral is set in the 1870s.
Factual error: Number 6 wakes up to find the Village deserted, but the central plaza fountain is still running - until he looks at it from the bell tower, when it's suddenly off. The Village fountains never appeared to be on timers (they were always on, day and night), and no one is there to turn the water off, yet it's somehow still off when Number 6 returns at the end.
Factual error: When David Vincent lands at the airport, a sign there says, "Welcome to San Diego." When Vincent exits the airport, it says, "Maricopa Airport." There is a Maricopa in California, but the episode takes place in Arizona, as indicated by the license plates on the cars and mentioning the city of Tucson close to the town the episode takes place in.