I have been smoking on my kettle and decided to upgrade to the WSM 18.5". I plan on smoking an 8 lb butt and two racks of ribs this weekend. On the kettle I typically bank the charcoals and add 12 lit on on side. I assume the same minion concept is what I need to do. My question is approximately how many unlit coals? How long will it take? On the kettle I mop every hour. Does this still apply? Would love to have a good smoke as I am having over a bunch of friends.