Privately-owned Irish property company, Shelbourne Development, has unveiled revised plans to build a 2,000 foot (609 metre) residential tower in Chicago. Shelbourne purchased a site on the shore of Lake Michigan for $64 mln (EUR 48.4 mln) in July for the 'Chicago Spire', which would be the tallest skyscraper in north America and the second tallest residential building in the world.