A group watched as cinderblock-sized hunks of gum inched along a conveyer belt before being pressed into sheets and sent down the line. There was mint in the air — a lot of it — and the unaccustomed eyes of visitors watered with the scent of Wrigley’s gum. Made up of local business owners, community leaders and members of the media, the group got a rare glimpse Wednesday into the inner workings of the Wm.