On the 2nd of July 1961, there were four Ferrari Sharknoses at the start of the "Grand Prix de l'ACF": # 16 Phil HILL # 18 Richie GINTHER # 20 Wolfgang VON TRIPS # 50 Gian-Carlo BAGHETTI From your picture, it seems indeed that this is car # 50. Cars # 16, 18 and 20 started all three from the front row. Baghetti started from the 5th row and won the race.
You can always learn something new on Ferrari Chat for me, I did not know that Fantuzzi built the bodies for the 156 Ferrari Sharknose as well as the Maserati 250F Piccolo lightweights.