When the Palm Beach Mall opened 41 years ago, it was the largest enclosed shopping center in the Southeast. Now the West Palm Beach shopping center is little more than an eyesore. The 1.2-million-square-foot mall, just east of Interstate 95 on Palm Beach Lakes Boulevard, is filled with unrecognizable merchants and empty storefronts. Many tenants, including Dillard’s, are leaving the mall ahead of a major renovation. The mall’s owner, Indianapolis-based Simon Property Group, said three years ago that it would reinvent the Palm Beach Mall, but it only recently provided details. Simon Property’s plans call for 1 million square feet of general retail space, a 290,000-square-foot furniture store, 300,000 square feet of offices and 500 residential units.