The gold 1967-68 Ford Mustang coupe with white vinyl top 'studio car' is seen in the fight scene. It appears in the background of many episodes and was apparently owned by a member of the film crew.
The woman reporting her purse stolen from her car is driving the famous Peugeot used by Columbo in Columbo (1971). Both shows were produced by Universal.
At the fight scene, there are two cars in the background with their branding obscured. The first one is a 1969 Ford Custom with the Ford lettering above the rear bumper covered with silver tape. The second one is a 1967 Ford Mustang coupe with the Mustang lettering on the trunk lid covered with silver tape.
Paper hanger is slang for someone who knowingly passes bad checks in whatever form (forgery; insufficient funds in one's own account as two examples), and/or counterfeit money.
Tracy Boys is most-likely slang for police detectives in reference to Dick Tracy.