When Camerero sprays binaca in his mouth in his car, he rolls his tinted windows up before exiting. But when he is shown next to his car, the windows are open.
The actual gun used in the film is a Smith & Wesson M76 9mm machine gun without the barrel shroud and not an M3 .45 caliber "Grease Gun" made by GM Guide Lamp Division for WWII use. The omission of the barrel shroud gives the appearance of an M3. If one sticks to the story line, the M3 magazine held 30 rounds .45 ACP and cycled around 450 rpm. This is sufficient to inflict the damage and wounds shown in the film.
In the morgue scene, early in the film, there are a few "corpses" breathing. On one corpse, the toes curl.
The Anthony Zerbe character is Lieutenant "Styner" according
to his desk nameplate, but "Steiner" in the closing credits.