We keep our single crib board in place when the weather suits. Our cover atop doesn't slide like many, but folds up and forward on a hinge. We easily sit on the cabin trunk from the top step and swing our legs over. It's a swift and casual move.
Our single crib board is three pieces of polycarbonate with the center piece cut out to accomodate the stained glass piece. This lets in much nice light and the whole unit slips into a slot next to the steps when we want more breeze.