I just bought my large BGE a month ago and have enjoyed using it. Tonight I am going to start cooking a 8# Butt (bone in), I am using Ozark Lump Charcoal.My question is, how much Charcoal do you normally put in the BGE for an 8# butt cooked at approx.225-250 deg. I have read here that it could take up to 16-18 hrs. depending on liquid content.I have also read that you fill to top of fire Ring or is it top of fire box? I have layered it with large at bottom and medium in the middle and smaller on top. Have used about 3/4 of a 10# bag and am up to top of fire box. Does this sound about right? Thanks for any help you can give.