Smooth sided filon or fiberglass is doable but a real chore assuming you know what you’re doing. This ain’t a first timer experiment type of task imo.
On corrugated aluminum I’d probably burn the camper down and collect insurance before I’d even consider replacing the decals.
And I say this being relatively well versed in installing decals, pin stripes, vinyl wrap, clear bra, etc.
And can’t use any of the good solvents on powder coated aluminum like you can on gel coat.
Also gotta be more careful with an eraser wheel on pc Al.