Hilmar Pedersen - died in Deluth 1968

My father’s uncle Hilmar Olaus Pedersen, born in Norway 26.4.1884 in Trondenes went to US in 1903. 3 of his brothers did also go to US. One lived in St. Paul and 2 others in Seattle. Hilmar worked in construction activities, building bridges aso. Last time the family heard from him was in 1919, his sister in Norway got a letter from him, he was then working at great bridge, later she heard that there was an accident at this bridge, several persons died. Bothe the family in St. Paul, Seattle and Norway tried to find something about Hilmar. The Salvatore Army tried to find him with no success. All his brothers and sisters died without any information about their loved brother Hilmar. Some years ago I got a message from US that some information about Hilmar was found at Social Death Index. Hilmar died in Duluth in Minnesota in 1968 (Social Index 474-03-1940). Information from US tells us that this is the right Hilmar. I have tried to find something about Hilmar with no success. Was he married? Did he have a family? Where did he live aso? I want to find out something about his live during periods from 1919 to 1968. His brother lived in St Paul. He didn’t know anything about his brother lived in Duluth. Is there any one in US who can help me with the history about Hilmar? With best greetings from Norway Edd-Magne Torbergsen