It will be interesting to see the actual solution to this one. The vehicle pictured is, without a doubt, the car that began life as the American Ford Cardinal which was given as a fully-finished design to Ford of Germany when Dearborn decided not to make the car in the United States. It was produced there as the Taunus 12M, or P4. That much, we all know and can agree on. However, the particular version of the car pictured is slightly different and proving very difficult to positively and unequivocally identify.
What a great and interesting puzzle, Djetset, and well done. I can see what's different, but damned if I know what it signifies. Time to keep looking!