I forgot to mention one other note:
The 6.9's seem to "rattle" louder, which make some swear they are a truer diesel...
Ford is the originator of the assembly line idea, so I imagine there are "KNOCK OUT" plates or spaces on either side just for that. A spot of sheet metal and a saw ought to take care of any problems, and I suspect the same is true of the frames as well.
*A plasma cutter would be a terriffic tool here...
Bronco's are an F-truck with a coach body. Every part of it is the same from the seats forward. If I'm wrong, I owe you a liter!
~and I expect you to hold me to that if and when I come down under next...