We have driven from Orlando to Fll, often, and it takes about 4 hours, so you need to factor more time in getting from the west, to the east coast. A rental car would make the most sense to me, and, you can return it at Fll airport, then get shuttled to the port.
If you get off the ship early with no custom issues,and have a smooth drive over, you would probably board mid afternoon, for a 4/5 o'clock sailing..bring some pepto
Trip, with her book & tea!
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