Pretty much, unless the seller has the exact same model and year truck, everything will be different.
When I brought mine home, I used stake pocket tiedowns and 2" load straps thrown right up over the roof of the camper, but it is a light camper. I wouldn't have done it that way if it had been a heavy camper.
The straps did rub a bit on the wall of the camper, marring up the graphics in one small area. It annoys me every time I look at it. You'll probably want to take some measures to prevent rubbing if you decide to go this route.