I could see Luigi's or even parts of the main street of Cars Land turning in to a generic Route 66. This could still include the drive-in restaurant and create a smooth transition from Cars Land to Paradise Pier.
It will still be there, because the movie itself comes from Route 66. Maybe they'll tone down some of the characters from the movie, like rename Sarge's hut or Luigi's flying tires, but it can still be essentially Route 66 land. Besides, 50 years from now the Disneyland on the moon will be much more fun because of all of the cool rides they can do because of the lack of gravity, so no one will care about Cars Land by then anyway...
Disneyland Cast Member
1996 - 1999