When Adam-12 pulls over the salesman, the camera prominently, and exclusively, shows Malloy unbuckling his seat belt. Seat belt laws were relatively still new with the law passed just three years earlier prior to filming. Jack Webb was on top of things showing the series contending with new laws such as this one and the Miranda Rights act.
The Gold Mustang crew car makes an appearance when the officers are on their way to the fist fight.
390 = drunk.
NCIC = National Crime Information Center.