Dear Maryellen, I decided to have another look at the Ellis Island records and found that Luigi Plos when to the US the stay with his brother Dante plos in Chicago. So Luigi can't be Dante! So I searched for a Dante Plos with no exact spelling and Bingo! You will be glad to know he was not married.
Ellis Island record reads:
First Name:Dante Last Name:Plas (spelling error "typical") Ethnicity:Italy Last Place of Residence:Maiano, Italy Date of Arrival:January 17, 1921 Age at Arrival: 20y Gender: M Marital Status: S Ship of Travel:Belvedere Port of Departure:Trieste Manifest Line Number:0018
He apparently went to stay with his uncle Giocondo Diplati at springfeld Ill. Note: Make sure you view the original ships manifest (also click to enlarge manifest)always read the original for lots of info!