Bozeman tried to dig itself out of a two-goal hole, but Great Falls held on for a 2-1 victory.
The win by Great Falls clinched the best of three series at 2-0.
Larson was all over the ice for Great Falls, as he had two goals in the win.
Jake Stephan made 24 saves for Great Falls on 25 shots. Great Falls incurred six minutes in penalty time with three minors. Stephen Frank rejected 22 shots on goal for Bozeman. Bozeman incurred six minutes in penalty time with three minors.