When Thing looks in the phone book, he is a left hand instead of his usual right.
When Morticia is charming the snake, there is a shot of Gomez looking with interest. The shot has been flipped. Notice his hair is parted on the wrong side and the chain on his jacket hangs on the right instead of the left side.
When Gomez and Morticia play the pungi, their finger movements do not match the note changes.
The strings manipulating the magical rope as Morticia and Gomez play the shehnai can be seen.