I've learned to enjoy cooking flats... Trim off very lightly. I Inject the night before with Beef Broth, Worcestershire sauce, Garlic and Amesphos. Then Season with the rub or combination of spices of your choice. Cook fat side up for two hours then flip. Pull at 160 and wrap in foil with a 1/2 cup or so of water to add moisture. Then pull at 200. I usually cook between 225 and 250. Where I had my biggest challenge and lost a few Briskets was at this critical point that follows pulling. When pulled at 200, drain off the juice into a bowl and let the brisket rest uncovered for at least 10 minutes so it stops cooking. After 10 minutes, place in pan or foil, cover with the poured off juices and let rest in cooler for at least an hour. Total time is about 6 to 7 hours. Good Luck, may you find that great Brisket on your next Smoke.
Lang 48 Patio, WSM 22.5, Weber OTG, Weber Genesis, Stok Tourist & Hot Coals Thermapen