A panel assembly includes a housing defining first and second troughs. Each trough has an arcuate surface. A panel is pivotally attached to the housing. The panel is moveable between first and second positions. The panel includes first and second protrusions. The first protrusion extends in the first trough adjacent the arcuate surface of the first trough. The second protrusion extends in the second trough adjacent the arcuate surface of the second trough. Movement of the panel between the first and second positions moves the first protrusion over the arcuate surface of the first trough, and moves the second protrusion over the arcuate surface of the second trough.