Ardagh Group, the packaging multinational taken over by its lenders from its former controlling shareholder Paul Coulson last year, is putting its crown-jewel metal cans unit up for sale. In a filing to the New York Stock Exchange this Thursday, the Luxembourg-headquartered, US-listed company Ardagh Metal Packaging SA said the ultimate owner of 76% of its shares, Ardagh Holdings SA (AHSA), had appointed Evercore International Partners LLP as financial advisor and Kirkland & Ellis International LLP as lead legal advisor to prepare the deal. “In this regard, the board of AHSA has instructed its advisers to prepare for a potential…