Just to let you know - I am also researching some Zupa/Zuppas (Buffalo, NY) and this group of Italians came from a fortress town named San Fele, Italy, outside Naples. Good luck on your journey!
(PS. Have your bio parents passed away? If so, try contacting the funeral homes or cemeteries and see who made the arrangements. Get a death cert. and see who submitted the info, name of cemetery, doctor, etc.)