In the scene where Lieutenant Buntz is backstage before his television court appearance, the mechanical Gunslinger that Mick Belker drew against in an arcade stake out in Gung Ho (1983) is visible.
When Lucy begins to run to the smoke shop to help Joe, she passes a silver Monte Carlo parked in the street. This car is seen many times in many different episodes, usually driving.
The TV show's Bailif's uniform patch clearly says Chicago identifying the city HSB is set.