On the surface Shannon seems as though he should knock Ingo onto a different continent. But then I remember the Darroll Wilson fight.. I'd still favor him but its not a given.
While Ingemar is the overall better fighter, this might be a bad stylistic matchup for him Either Ingo UD or Briggs KO
Prime Briggs bombs him out. Old Briggs might do it too unless he gasses and becomes a sitting duck for a barrage of rights and loses an ugly decision.