I had an extra propane bottle mounted on a camper. Got the mount and cover at a local camper supply place. Since it was an older camper I was not worried about it doing damage. I had that camper for 5 or 6 years and the rack never hurt anything.
2016 3500 HD Durmax
1994 S and S 9.5' Camper (SOLD)
1999 S and S 9.5 Camper