Update - We made it to Fort Wilderness from South Central Texas. I10 - I12, highways were not all that bad through LA, MS, AL but the road construction, wrecks, traffic back ups and just the volume was ridiculous! Went through the tunnel at Mobile AL. At one point we sat still in traffic for over an hour. Florida I10 was a breeze, connection to I75 and going south Florida was horrible traffic, several traffic back ups 10-15 mph for 20-25 miles. Florida Turnpike to Disney/Epcot wasn't too bad.
Now getting into Fort Wilderness - DO NOT use GPS, terrible, they all lie and will get you lost. Disney sign posts directing you to Fort Wilderness are terrible, just terrible! We got lost several times, at one point I had to try to turn the rig around backing up, right angle turns in a business parking lot and we are 53+ feet, not an easy task with traffic, finally just right inside the Disney complex, I parked in the street and refused to move until I got clear directions and even then it was a pain! They get you into the far left entrance lanes of 5 lanes, then all of a sudden you have to move over all the way to the right lane to take the entrance to Ft Wilderness. The wife and I had a few words spoken between us!