Hello Frank : Greetings from accross the Detroit River eh !!
We have made the trip down the I-75 quite a few times, however, we'd never make the trip without the guidebook...
Along Interstate 75, by Dave Hunter
The "Along the I-75" guide book takes all the guesswork out of what's coming up...it allows you to plan your stops in advance...& best of all it gives you TONS of peace of mind to be able to have things figured out before you pull out of your driveway !!
Each page is about 30 min of driving time, so you can easily see how long till the next destination...Walmart, or Cracker Barrel.
Good luck to you...& BTW, where's your intended destination in Florida ?