Sounds good, Don. One other thing to be aware of, which, considering your experience, you probably are, is that you probably want the lightest/least obtrusive frame possible so you don't impact air flow too much. I would also put sizable gaps between the firebricks (maybe 2") for the same reason. The big guys attach the firebrick frame to the ceiling, which get's it away from hot air coming up the side vents and down towards the pizza (like an M pattern), but I think that's more trouble than it's worth for your setup.