The Engine 51 arriving at the Oceanland Park rescue is not the real Engine 51. Based on the Los Angeles County decals not being centered on the doors and the sliding jump seat windows which Engine 51 did not have. A different Ward LaFrance is used in this segment, possibly Engine 106 or Engine 53 due to their proximity to Marineland.
During the scene in Dr Bracket's office, the wide shots show the collar on Mrs Winslow's coat laying flat. But in the close up shots, the collar is turned up behind her neck.
When Station 51 is dispatched to "Oceanland," the time out is given as 1630, or 4:30 PM. There are very few cars in the parking lot when they arrive, but as the rescue progresses the parking lot gradually fills up. In reality, "Oceanland," really Marineland (which no longer exists) would already be open and the parking lot would have had lots of cars in the parking lot by 4:30 PM. They had to have been at the park a lot earlier in the morning given the emptiness of the parking lot and the morning overcast when they first arrived which was giving way to sunny skies as the rescue progressed.
The shadow from the helicopter filming the tower rescue is visible on several shots, most notably when the ambulance attendants are loading the tower rescue victim into their vehicle.