Frank I have done a couple of BC Turkeys, up to 17 lbs. I use a BGE rack, not quite the same as the one in your post but it should work and I lower my top rack 4" so that I have the clearance I need for the dome. Here's a photo FYI.
That's also a good looking bird.....so you don't just cook the turkey on the bottom rack? Would that be too close to the fire? And how do you lower the rack ? set it on soup cans or something like that? I'm thinking I can prob'ly get by with just my old beer can chicken rack.....why buy something new if I don't need it?
I'm of the opinion that beer can anything is a waste of effort. I've done them a beer can and a regular chicken at the same time and no one could tell the difference when eating..........................d
To ensure you have no red near the leg/thigh bones you need to get the thigh up to 185. I spent years trying to convince my wife it was cooked even if it looked like that and finally gave up, now my chicken is well done in the thighs.