Following olsen-ohlsen to Minneasota

Hi, I've located my ancestors coming through New York Port June 1868. Niels, Helene, mauritz, henriette, Ovidia, and Nora. What would be the best way to follow their path to Minneasota[?]. I know they were listed in the 1880 Ham Lake Census. Their ship directory listed Chicago on the S/S Argo 1 . Any ideas would be helpful. [:)] Kim