I would leave them alone. They know where their stores are if you don't juggle them around too much. You could take the bottom box off, but it doesn't really make any difference if they are at the top anyway. Mine spend most of the winter at the top. You can, as Finsky suggests, move some frames where they contact the cluster and they will find those easily enough. But unless you have some extreme cold for long periods (unlikely in MD), they will find it anyway.