Visible crew/equipment: In "Playing The Ponies" (1937), a man eats a handful of hot pepperinos, and his mouth is burning. He quickly drinks a large container of water. The hose that drained the container is visible below his right arm.
The Three Stooges Show (1960)
1 visible crew/equipment mistake in show generally
Other mistake: In "Violent Is The Word For Curly" (1938), the Stooges are mistaken for college professors. They are teaching a group of students at the all-girls school Mildew College to sing "Swingin' The Alphabet." During the song, the girls sing "Curly's a dope." The dean had introduced the three men as Professors Feinstein, Frankfurter and VonStupor - so how did the girls know Curly's name?