Very nice looking custom smoker Peeps. Seeing yours, I can hardly wait to get my Lonestar Grillz Vertical Offset. I hope you get the lid issues worked out. Did you have a hole cut in the side for wiring your probes?
Look into Baking Steel for Pizza. I've had several Pizza Stones crack and eventually break. I'm either going to get the brand "Baking Steel" or have Chris cut me a piece of 1/4" A36 to put in place of the firebox cooking grate when I want to do Pizza. It has far better conduction and thermal mass than a stone and will never crack or break.