What "makes" a 66 Barracuda a Formula S ??

Oddly enough, my 273 4bbl actually came off the line with the "Charger 273" decal on the air cleaner.... it was made at Hamtramck (Dodge Main), so either a sorting mess up on the line, or a low stock on the Commando 273 ones on date B10 (November 19, 1965) I always wondered if there was a Dart somewhere with "my" Commando 273" air cleaner... :)
There is probably 2 baskets of air cleaner tops. The assembler grabbed the wrong one. That stuff happened a lot back in those days.