I've not done it on an RV before, but have several times on my home and shop. Hopefully not too much different.
It's about the same but smaller bits. I'd research the framing with a stud finder or small drill bit. You could install pieces of hardwood between any vertical framing. Or aluminum, but you may have a fastening challege.
I buy aluminum profiles at
Discount Steel. They are local to me but do ship.
If I build something that really needs to look good, I shop here at
80/20 Inc.. The extruded aluminum is available with a full line of different fasteners and accessories. Big guy's Tinkertoys.