Brad Garrettat a smidge over 6'8", is about nine inches taller than Jackie Gleason was. To compensate, other actors who shared scenes with Garrett wore platform shoes that would make everyone seem proportionate.
Gleason is shown being fired from Navy Blues in 1949 or 1950. In real life, the film premiered in 1941 and he was not fired. Also, Cavalcade of Stars was not his TV debut. He starred in the short-lived series The Life of Riley.
The opening scene is eastablished as being 1924. When Jackie and his father return from the theater, Herb Gleason offers Jackie a nickel with Monticello on the reverse side - a Jefferson nickel. This design wasn't minted until 1938.