I remember back in the 60's when it was stylish to hide the gas filler hole under tail lights, license plates, etc. I had a '71 Nova with it under the license plate. The problem was that in that year, the plate was below the bumper which made the filler too low. You didn't want to be behind it when the nozzle clicked off because it would always splash on your legs.
I think the govt put an end to having the filler in the rear of the vehicle because it would piss gas if you got rear-ended. Not a good thing to have gasoline squirting out of the rear of the vehicle during a collision.
