Other mistake: When Squad 51 is dispatched to "possible heart attack" the address is "91st and Formosa" (the 'Black Tower' can be see behind the Chevron sign when the squad rolls up), and later when they're dispatched to "person caught in mailbox" the address is "Beverly Blvd and Main." What's funny is that the two incident scenes are filmed at the same corner of the intersection, with Universal's 'Black Tower' nearby. Have a look.
Other mistake: When Roy and Johnny are working on the squad's engine, while Johnny's lying on the mechanic's creeper, Roy is holding a spray can with white tape wrapped around the top of the can, so the brand name would not be visible.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.