You should know by now, if there’s an opportunity for a brief misdirect—in the spirit of sensationalism—expect it. As you’ve, no doubt, already figured out, that is not a Buick Century proposal or even a Buick. It’s actually a Ford Mustang design study from the middle of 1976.
Though not very aggressive-looking, it is a fairly attractive design with a short deck and long hood (which is likely enhanced by the forward-leaning edge of the hood). Ford said this clay buck was used to test out detail variations with inserts, such as the side vents around the rear wheel well.
The wheels look to be off of a then-current production Mustang and the badge on the right front fender actually reads “Mustang II.” Curious if that was a placeholder or if they’d considered keeping the name around.
There were some other neat renderings hanging on a wall in the background of the shot. Below is a closeup of that area.