Here's a little more on the setup I use to use before the KP.
1 full chimney of kbb lit.
Pour lit kbb in the kettle around the edges. I usually went 3/4 the way around.
Added a few more unlit kbb on top of that and let the grill preheat.
I could reach air temps above the stone in the 550 range and the stone, I believe, around 400-450
Throw the pizza on and watch through the lid vent.
Looked at the bottom of the crust around the 3 min mark.
Rotate the pizza 180 at the 6 min mark and finish cooking. Usually another 5-6 min.
My stone was sitting on a smaller cooking grate elevated with ss bolts.
So, I have a 16.5 in diameter stone and tried it on my 18. I believe the diameter of the stone limited the amount of heat above the stone and couldn't get the pizza to cook properly on top. But, this size stone works well on the 22.
There are different ways to do this. You just need to give it a go and see which method works best for you.