My mum drove a 500 - it was a 1972 left-hooker bought when my dad was posted to BAOR in Minden, I think, but she kept it until it was stolen and wrapped around a lamppost (a triumph of poor acceleration outdone by poorer brakes?) in around '76 at which point it was replaced by a RHD 126. Both were red, and were known as the LRF (Little Red Fiat)
I don't remember much about it (except that I once leaned forward from the back seat and pulled the starter lever when the car was running, which incurred a loud graunching noise and much parental wrath), beyond the fact that with both family cars being imported when we moved back to the UK, the Fiat and a Simca 1100 Estate had consecutive registrations - NPK 193L and NPK 194L.