You would have to upgrade the wiring also. Don't you have a battery in your camper? And it's charged from the truck correct? I believe the charge circuit from the truck is only around 30 amps, and slowly charges while you are driving. Unless you have some other special need for a higher amperage alternator.

I have never done the swap, but like you said it was an option, so I am sure it could be done. I cannot tell you though, if you would need a new alt bracket. But I am sure you would have to upgrade the wiring to the alternator, and if you do have a high amperage device you are running, it will need it's own wiring, not the truck's original wiring.