Branson, i go half way up the ring. for a long cook like that i have a wiggle rod which is a .125 diameter rod with a 2 inch bend on one end. you can reach thru the lower vent and stick it thru the grate holes and give it a shake to avoid any blockage of ash. i do this halfway into the cook, and also open the egg and push some of the lump around the perimeter toward the middle. this will keep the temps from dropping and also avoid center burn which seems to happen every 10 or so butt cooks. a coat hanger works for this as well. 250 is easier to maintain than 225 and gives you just a little more time to catch a fire that maybe failing