It is one of 275 produced Dart 270 4 dr sedans with 273x4 bbl and one of 254 Dart 270 4 dr sedans with auto on the column. This one is assembled September 11!
A rare car indeed!
I found a further breakdown of production numbers for the 65 cars. I haven't found that site since. I had a 65 270 sedan (post) car with a HP 273 and a 3 speed on the column. One of very few if I remember correctly.