Unbolt the strap that hangs down from the panel, then get a flathead screwdriver or something similar and pop the panel off. Once the panel is popped off, lift it straight up to remove it from the window area.
Inside you will see a black metal panel, with a couple control boxes and wires. Disconnect the wires, and unscrew all the bolts holding on the black panel. Once that is removed, you will have access to the back of the hatch when the window is rolled up.