After the fight at the bar, Mannix holds onto a set of bull's horns while one of the Chicanos talks to him. Near the end of the conversation, his hands are near both ends of the set of horns, but when the shot changes slightly, his right hand is suddenly holding them near the middle.
When the police car that brought Mannix and Carlos to the station is parked, the license plate seen is a dealership license (DLR 4). A police vehicle should have a California "Exempt" plate.
Mannix returns to his car. While he is just about to open his driver side door, he looks at his driver side door mirror. The camera does a close-up shot of the mirror where we see the face of a man in a window of the apartment building across the street from the car. This would imply that the man in the apartment window would be located at some distance behind his car. The camera then does a long shot including the building and the car. At this point we see the man in the apartment, except that the man in the apartment is located towards the front of the car.