The car approaching the checkpoint during the opening credits is a 1954 Lincoln Capri convertible. Matthews' patrol car is a 1956 Dodge Coronet. The abandoned Highway Patrol car is a 1955 Mercury. The car Larry's brother steals is a 1956 Plymouth.
When Larry steps out of the phone booth after calling Miss Nielsen, the street sign shows that the bookshop is located in the 7300 block of Melrose Ave. in Los Angeles.