I think I heard somewhere that Harley was putting a 2 cylinder flathead in their motorcycles. As far as putting a flathead in modern truck, it would probably need to be redesigned to fix its quirks. I for one, would love to see a flathead with four exhaust outlets on each side. But by the time the flathead was "updated" it would no longer be the flathead we know and love. It is nice to dream though.