1979 marketing for the film heavily emphasizes Gene Wilder's role in the film, with little marketing of Harrison Ford's supporting role, despite Ford having been in the blockbuster Star Wars: Episode IV - A New Hope (1977) two years earlier. When The Frisco Kid was released on DVD, the cover was a blow up of Ford's face, with Wilder relegated to a small corner of the cover.
In his autobiography, Gene Wilder says that John Wayne was offered the part that was eventually played by Harrison Ford. Wayne loved the role and was eager to work with Wilder. However, an agent tried to offer Wayne less than his usual fee and the legendary actor turned the film down. This may be true, but it is actually unlikely. By 1979, Wayne was too ill with stomach cancer to consider film work, and he died later that year from the disease.
According to the specific version of the Amidah prayer that the rabbi says, it is possible to derive that he left the Amish village on a Thursday.
The opening credits are still being shown at the sixteen-minute mark.