I think I'm your third cousin and I live in London. My father is John Lewis Massarella (married to Diana Massarella, used to live and work in Doncaster, now lives in Surrey - they are both 87). His father was Lewis Massarella (married to Louisa) and Lewis's father was Giovanni Massarella. Our origins are also in Settefrati.
I think your grandfather Ronnie (of showjumping fame?) is my late grandfather's cousin - or perhaps his brother? - but he is closer to my father's age and I think they used to make ice-cream together... does that fit? My father then went to run Lyons ice-cream in London (which is why I'm a southerner!).
I know someone has done a very detailed family tree of our whole family - I don't suppose it's you, is it? I would love to see it if you have.