The flamboyant developer made his offer in a ”Dear Ed” letter to Mayor Koch dated May 28. ”For many years I have watched with amazement as New York City repeatedly failed on its promises to complete and open the Wollman Skating Rink,” he wrote. ‘Should Take No More Than 4 Months’ ”During this six-year period,” he said, ”I have constructed major hotels, apartment buildings and, in 26 months, Trump Tower, a highly sophisticated and complex mixed-use building containing shopping, offices and apartments. Building the Wollman Skating Rink, which essentially involves the pouring of a concrete slab, should take no more...