We're doing just the opposite...we're on the Mariner 7-day Eastern Caribbean cruise leaving June 24th. I added 4 nights at WDW before the cruise. Our pre-cruise trip started out as one night near the port and has become four nights at the Yacht Club with the
DDP and Park Hoppers, so I'm out of control in my planning!
I haven't done this before so I don't have any real tips for you. We did find that a Budget rental car with a pick-up at Orlando and a drop off in Cape Canaveral right by the port was very economical. We only paid around $100 for the five days.