Then-New York State Governor Nelson Rockefeller and his family visited the set when this episode was being filmed. In a few years, Rockefeller would ascend to the vice-presidency under President Gerald Ford, who assumed office after Richard Nixon's August 1974 resignation in the wake of Watergate. A brief description and a photo of Rockefeller's visit to the set can be found in Barry Williams' book "Growing Up Brady."
The ghost town set is exactly the same as the set on Gilligan's Island during the dream sequence where Emily the duck is being chased. Gilligan played the Sheriff in the dream. Jim Backus played an identical character in the dream sequence as he does in this episode.
This is the only episode when the dining room curtains are opened and we see this view of the yard. Mike opens the curtains to show the kids the camper.
As well as the Emily the Duck episode on Gilligan's Island, Jim Backus plays the same role of the Prospector in the dream sequence in The Sweepstakes. Sherwood Schwartz produced both shows.
The ghost town set was on the Paramount lot and used extensively as Virginia City on Bonanza seasons 1-11. Note the infamous "Paramountain" at the end of town.