Everything is curved on these new trucks, including the bed. For that reason, I doubt that a Ford cap will fit a new Dodge. Even the tailgate is curved.
On my '91. 5 W-250 Dodge, I purchased a metal cap that seems bullet-proof. So, when I bought the '03, I went back to the same manufacturer. They would not build a cap for my truck & showed me all the curves. It is hard to put those curves in a steel cap but, fairly easy in fiberglass.
Joe F.