There's also a Muscle Car Museum in Punta Gorda but I've never been and I'm not sure how far away that is and its mostly or possibly entirely GM only. Here's their website. http://musclecarcity.net/contact/
And unfortunatly, you are a couple weeks too late for the Spring Turkey Rod Run show in the Daytona Speedway infield in Daytona Beach. That is a huge two day event. http://www.turkeyrun.com/Turkey_Run_Home.html
Too far away maybe but theres the Palm Beach Barrett Jackson Auction while you are in Florida as well. http://www.barrett-jackson.com/