If you get a cab, ask the driver to take you down Bayshore Blvd. on the way to the airport, but if you could rent a car, it may be the best thing to do. 1st, stop at the Columbia Restaurant at Ybor City, and you can see some of the points of interest in Ybor like the historic Cuban and Spanish clubs. Near the airport, take a leisure drive down the Causeway and continue to Clearwater beach. That would give you more than enough time and be back to the airport by 6.