Is it me or do the ladies in those pictures all look like they are planning to kill their husbands for the insurance money?
That chrome trim that runs up both sides of the hood and across the doors is the easiest way to tell. Unless of course the badges are still on the car that say deville or fleetwood.Leather wheel was optional on FW, also.
Besides the roof vinyl trim/side window treatment, the most obvious difference is trim. FW has wider stainless rockers that come up on the door, and has chrome trim on both sides of the hood, while DV has a single chrome spear down the center. FW gets wreath around trunk emblem, DV gets a V.
This will help:
I have a Coupe and mine doesn't have this, then again it's an 1980 Coupe. Later years yes, they had the single chrome molding down centerThe easy way to tell is the size of the padded roof. Coupe deVille padded tops were completely behind the rear quarter window, Fleetwood vinyl tops started at the B-pillar and surrounded the rear quarter window. Further, Coupe deVilles had a single chrome molding down the center of the hood, where Fleetwoods had chrome on each side of the hood bulge. The car in the photos is a Coupe deVille.