Even though the 2011 Shelby GT500 carries a base price of $49,495 without any options ticked, Ford has already received more than 3,000 orders for the 550HP Mustang since the car was announced earlier this year. But despite the sales success, the Deaborn-based automaker said today that U.S. sales of the 2011 Shelby GT500 will be limited to just 5,500 units for this model year.