Kohldad,
Don't forget to measure the height of the bed in the old truck, so you can check the height on the new truck.
GM played with box heights between 2006 and 2014. I didn't realize until I was loading the camper for the first time on the new truck and I had to jack the camper back up so I could get a piece of 3/4 inch plywood to keep the camper from riding on the truck bed rails:S
They also changed the shape of the box, with rounded corners instead of the more square corners.
Hopefully Ram designers haven't changed things too much.
Brian