As far as the top goes, I seriously doubt it. The 2G trucks are square at the front of the bed and the 3G are curved to contour the cab and also the cabs have different silouettes.
As far as the back seats go, if it wasn't for the body change I wouldn't have bought a CTD. It's only the 3G back seat that has enough room to place a car seat in the back and still have everyone comfortable. Also, some of these other guys stated that there isn't as much room as the four door ferd or chubby. I like that fact because the rear doors significately shorter (horizontally) and therefore when the kids get out of the back there is a much less chance of their door hitting the car next to us.