A Michigan man is planning to keep some of the 160 bowling balls he found while demolishing the back landing his home.  David Olson found them under the stairs he was taking apart earlier this month.  He didn’t think much of it at first until he realized there was “an entire gridwork of them.”  Olson noted the home was built in 1959 when a Brunswick Bowling Products factory was operating in Muskegon where he lives.  Former employees told him it wasn’t unusual to take unusable balls and use them for construction projects.