Planning a Route Back to Illinois

I'm planning the route from the RV dealer to my home.

I am picking up the RV in Seffner, FL (near Tampa). If everything is ready for me on time when I get there, I should have 6 days to get home. I can take my time and not have to drive 8 hours a day.

I want to stop at some beaches. I will not take the default route through Georgia and Tennessee that the map programs suggest.

I ordered a copy of Microsoft Streets & Trips with the GPS locator from Amazon, I have to get it installed on my Netbook before Tuesday. I also have to stop at Sprint and get one of those Wi-Fi devices so I can have access to the internet all of the time.

I'll go through the panhandle of FL and through the southern end of AL and MS. Does anyone know what the Mobile (Alabama) Tunnel is?  I probably need to make sure I can drive an RV through there. 

Then head north through MS, and keep going north...
This route is 295 miles longer than the other way. Of course, all of this is subject to change......... depending on time and weather.

I thought I would stop in these cities and probably some others:
Port Richey, FL
Panama City Beach, FL
Ocean Springs, MS
Bay St. Louis, MS
Tupelo, MS
not to sure which way to head after this, have to study my maps.

I have the Escapees 2011 Travel Guide. It lists discounted RV Parks, I don't think I'll be boondocking on this trip.

Any suggestions for things to see or places to stop overnite along this route?