Ms. Jones' (Margie Impert) first name is Madeline, but the nameplate in her window reads "Ms. W Jones".
In the opening scene in the barbershop, the customer picks up a copy of National Geographic from April 1982. The scene is supposed to be set in 1955.
When Magnum pulls up in the Ferrari to the Masters estate, the shot of the tires stopping, is in fact footage of the car taking off, but played in reverse.
Light stands, camera equipment and crew can be seen reflected in the door of the Ferrari when Magnum is leaving the airport (index 45:30).
When Magnum speaks to Earl's son Phil for the first time, Phil tells him: "My father is dead. My father's name was James. He has been dead for about two years." Later, Magnum speaks to Earl and tells him that Phil said to him, Magnum, that "his father got killed in Miami in a traffic accident 27 years ago." This is completely different from what Phil actually said, and no reason at all is given for this difference.