On the gauge, what is supposed to represent Full and Empty?

Is the two dots on either side of "1/2"? Or is it the actual letters, "E" and "F"?

My gauge doesn't quite go all the way to the letter "F" and goes past "E" when the ignition is shut off.

1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)