I will be doing 1-2 butts, and a 7 lb brisket at the same time, for Memorial Day. This is my 4th run at the WSM, and first time doing other than ribs or chicken. I plan to start around 6pm with the butt, and throw the brisket on at about 10pm in order to have both finish around noon on Monday. The problem I have here in AZ is the HEAT! Even with all bottom vents closed, the temps never get below the low 230's due to outside radiant heat. For a cook for 19 hours, is 230 - 240 too high?? Will adjusting the top vent help bring down the temp to the low 200's if I need to? Thanks!