How do you pop off the rear covers on the roof rack, in order to install the cross bars? Is it just press down on the back surface, then pull back?

I have a new 2007 Endeavor.

 

yes, the pop off. One side has a notch thing that will probably not work properly when you put it back on. When you put them back on, use a screw in the hole provided. If there is no hole, drill one. I have not lost a cross bar in the year since I did this.