I cook pizza on a screen in the UDS instead of a pan for crispy crust. I cook with all vents wide open and no diffuser so it is direct heat but up high ( same as the top rack in your WSM) and the temp is around 450 in my set up. The pizza cooks in 10 to 14 minutes. I rotate the pizza for even cooking. If you use a screen make sure you spray it with pam or it will be impossible to get it off. Don't ask how I know this.
3 UDS, One charcoal eating fire breathing home bulit trailer pit,