Johnny steals what looks like a brass postage stamp dispenser from Dr. Bracket's desk during the scene where Johnny and Roy are listening to a tape of a run by another squad. Apparently, this was a prank played by Randolph Mantooth that was never noticed until after the episode was broadcast.
When Squad 51 is responded to the big hotel fire, one of the other stations responding is Station 29. Station 29 is located at 14334 Los Angeles Street, Baldwin Park. This is an hour away to the NNW of Station 127, the station used for filming interior and exterior shots of the, then, fictional Station 51. The picture of Station 29 appears that it is a mirror image of Station 127.