By David McDonnell Sir Jim Ratcliffe wants to knock Old Trafford down and build a new home for Manchester United that will cost up to £3billion. The new stadium will be built on the existing Old Trafford site or on land adjacent to it, with the aim of making it the biggest and best arena in world football. New United co-owner Ratcliffe has set-up a task force to explore the options for a major regeneration of the Old Trafford area of Greater Manchester. The ‘Old Trafford Regeneration Task Force’ is chaired by Lord Sebastian Coe, includes former United captain Gary Neville and will bring togeth…