I had a job pumping gas as a kid (40+ years ago), and I remember those sneaky places where the gas cap was hidden on some cars. I was defeated only once, and it was the first time I had to gas up one of those ‘56 Bel Airs. I had to ask the driver how to find the gas cap.
Reminds me of that scene in “Vacation” where Clark is searching all over the new car for where to put the gas pump in, after searching everywhere his wife pulls open a hinge on the front hood and yells out “Clark- Isn’t this the gas tank?”.