Here's a bit more info. It seems like the lower right hand corner of the passenger side windshield is the correct location in most states.
https://cartype.com/pages/3635/gas_ration_stickers
and
https://www.fordbarn.com/forum/showthread.php?t=51196
https://americancarhistorian.com/gas...-world-war-ii/
Scroll down and you will see where the gasolene sticker was affixed to the windshield in the
The Big Sleep movie (1945) of Humphrey Bogart's car. No doubt that movie was filmed in California.
https://anotheroldmovieblog.blogspot...in-movies.html