Like putting a cherry on top of a sundae, cranes yesterday placed a giant bucket in its new home 70 feet up in the Hersheypark air, atop what will be the world's largest water-play structure. When the Derry Twp. amusement park reopens on Memorial Day, kicking off its 100th year, the East Coast Waterworks will be the centerpiece for the new Boardwalk at Hersheypark aquatic-themed area, which was announced in July.