posible used roof rack purchase

[WE7X]

Used factory roof rack installed just fine.
One thing I had not counted on, is that the roof has a crown from front to back.
As a result, a long board or pipe does not sit flush on the front and rear cross bars, it there are intermediate cross bars.
I had extra cross bars, so I installed a total of five....not thinking about, or noticing, that potential problem.
I can move the intermediate bars more to the front and rear, and reduce the effect of that crown, but it does not provide the added support near the middle of the load.
Most of what I carry is fairly lightweight and quite rigid, so the intermediate support in not a serious drawback. It is more of an irritation that I did not notice it in my planning this project, and a well centered cross bar seemed like such a good idea.
This will be my first attempt to add photos.