The amount of time your stone is preheated will change results. I would try it first by merely using this configuration with your normal workflow of getting the oven and stone to temp and bake your sicilian. If you see some results, but not optimal, try heating the stone longer or use a strip of foil along the back of the shelf where your stone is.
My cast iron/stone configuration was to get added heat on the bottom of the pizzas when I had to move my bake up from using the bottom shelf where my crust would burn on the stone. It would not brown optimally one shelf up, so I balanced the stone on the cast iron lid, and it was a good bake there. I do have pictures, let me find them.