That is a 2 door SEDAN not a coupe. The longer quarter windows denotes a sedan. My 51 special sport coupe has shorter quarter windows (almost triangles) which makes the passenger compartment a lot shorter. There were two coupe models, the top model was either a deluxe or a special trim called a sport coupe and the base model was only a special trim called a business coupe.
It looks like a 1951 with an earlier (maybe 49?) grille. The rear of the car, quarter panels, tail lights, etc. are clearly 51 or 52. The dash and interior are also 51 or 52. The trim on the front fenders, is 1951 only. And since the door trim lines up with it, I'd bet it's a 51 with 49/50ish grille.
