The title was taken from a Chuck Jones short Prest-O Change-O, a Merrie Melodies cartoon released on March 25, 1939, and reissued as a Blue Ribbon in 1947 by Warner Bros. It stars Happy Rabbit, an early form of Bugs Bunny.
Timmy switching bodies.
Mr. Turner in Mr. Crocker's body saying that he is gorgeous.
When Vicky and Mrs. Turner (Timmy) switch bodies, Timmy's mom is in a red dress. However, when Timmy's Mom (Vicky) says, "Ah! I feel old!" she is in her everyday attire. When the scene changes to Vicky (Timmy) taking the Body-swapping Joy Buzzer, Timmy's mom (Vicky) is in the red dress again.
When the veterinarian captured Crocker (in Doidle's body), he said "to the neuter scooter," which would indicate that he intended to neuter Crocker/Doidle. But in "Dog's Day Afternoon", Doidle had already been neutered.
Timmy: (in Crocker's body) I have to get home before exactly 4:00 or Cosmo and Wanda will poof in and reveal themselves to Crocker thinking he's me! Wait a minute, I can’t drive! Oh well, Not my van!
Mr. Crocker: (in Timmy's body) Doidle? What's a doidle?
Mr. Turner: Good heavens, son! Doesn't that hunchback ream of a teacher teach you anything?
Mama Cosma: ... Oh, Wanda, you're the greatest... disappointment of my life!