The original Fiat 500 was nicknamed the "Topolino" (small mouse) in Italy. "Topolino" in Italy is the name used for Walt Disney's Mickey Mouse.
Alis's father, Duilio, was a Moto Guzzi factory rider and when Fiat were looking for a sporty engine for the Fiat 500 Moto Guzzi built a prototype V twin engine and installed it in a car. Duilio drove it and declared that it was too powerful for the car. It would have required upgraded wheels, suspension and brakes which would have made the car too expensive. Fiat decided to go with Abarth who were already making tuning kits for the standard engine. The rest is history. No one seems to know what happened to the Guzzi Fiat prototype but it was probably destroyed.
The prototype Guzzi engine for the Fiat 500
Sporting the Guzzi test plate.