Thanks a million for your suggestions mate, really appreciated.

I'm doing my best to lay out at least a vague plan for our trip. It's been suggested that Memphis would be a better place to visit than Nashville. If we went that way it would probably mean we'd lose out on our Jack Daniels pilgrimage!!

At the moment our roadtrip is looking something like this (I got the car journey times from google maps):

Miami > Orlando = 3 hours 39 mins
Orlando > Savannah = 4 hours 21 mins
Savannah > McDonough = 3 hours 21 mins
McDonough > Atlanta = 0 hours 39 mins
Atlanta > Memphis = 6 hours 7 mins
Memphis > St Louis = 4 hours 32 mins
St Louis > Chicago = 4 hours 55 mins

All journey times will probably be increased by an hour or so in practice due to toilet/lunch/gasoline breaks along the way.

....I really wish we had more time for all of this! Retched annual leave limitations!