just for anyone's inquiry:
did 3 cooks with the Weber grommet mod with the highest pit temp @ 350degrees, so far it's holding up.
I would try to install this as high as one can of the bowl's outer rim lip to clear the grate, it's a tad above the grate for me and I try to keep the grate away from touching it. I'd try not to keep the charcoal bin under it and situate it far away from the grommet as possible.
I don't need to get pizza type of temps although I need to try my small vortex in this 22" to see if that produces more heat that could destroy the grommet. lol, don' know how high of a temp the vortex produces soo... . It'll do okay with the Weber bins and the sns as long as I place either one somewhere away from the grommet.