I had always thought Carcano's hotrod FIAT 500 was a "Topolino" that was produced from 1936-1955: Easy to see a Guzzi V-Twin behind that grill! Yet, in the 2002 Anima Guzzista interview with Ing. Carcano, he is quoted: "At that time I also built a V, 500 cc first and then a 600 cc. I put it on a Fiat 500. I remember that it gave me a lot of satisfactions. It was a motor, the 600, giving 36 or 38 HP. Exactly twice the output of the original Fiat engine, giving 18-20 hp. "