Adding to the information here, for those interested - FWIW
Basic infor is here http://www.pizzamaking.com/forum/index.php/topic,9342.msg139892.html#msg139892
BUT---Might be good idea, if looking to do za in shorter times on Weber, to make an oven out of a new 30 or 55 gal drum with some judicious planning. Less expensive than new Weber by many $coots. You want more infor, type in UDS (Ugly Drum Smoker) on line...Using drum will also preclude melting down your Weber, as I have nearly done a couple of times and also bake more than one pie at a time.