I sent away for his naturalisations papers but they are very damaged. I would be happy to scan and send to you but a lot of it is illegible. He was naturalised in 1864
I wondered about Giovanni and if he was related!
My connection is through Mary Jane Catherine Piffero (his daughter) she was my mothers grandmother. My mother says that she can remember her mother saying that he was a lovely man, quite small with a snow white beard. How true this is I don't know :)
I'm wondering if they had more than one farm? It's not a common name and there are a few farms popping up under that name in several areas around Echuca, Walla Walla, Culcairn. This makes me wonder if he did indeed first go to the gold fields and maybe did ok for himself allowing him to buy property.
Try searching http://trove.nla.gov.au/
for Piffero - a few things come up.