At least she knew that it had a 710 cap! True story:
WAYYYYY back in the day when I was clerking at a gas station a lady came in and asked if I had a funnel so she could add some oil to her engine. I gave her the small plastic one we loaned out to customers for that purpose. She said it wouldn't fit, it was too big. I was puzzled as it had a rather small end on it, we also used it to add ATF to trannies. I assured her it should work and followed her out to the fuel island to assist her if necessary. Yep, she was right! That funnel was way too big to fit into the engine dipstick tube! After showing her the 710 cap she was rather embarrassed. Seems she had seen her husband add tranny fluid down the dipstick tube and just assumed that's what you did with engine oil also.
Funny thing is, several people have told me of similar experiences over the years. All genders and ages too. In my day we all worked on our cars. Today the average teenager can slap a stereo in a car in under 10 minutes, but show him a spark plug and he's liable to think it's an electric suppository!