Max Air on a non-walkable roof

[shaner]

I have a Passport 2920BH. It is a non-walkable roof. So with that in mind, how do I install the max air vents? I thought about putting some boards across, but that seems even worse as the rook is rounded so the boards will put a ton of stress on the middle of the roof only.

I called the local dealer and they said when they install them they get right on the roof.

So what's the best way to go about it?