I don't know what grill you have, but on my 22.5 kettle, I split a full Weber chimney to both sides of my drip pan full of water. This photo shows my set-up pretty clearly. There is a half chimney on each side. I have my top vent about 1/2 open, and work my bottom vent to get 300-350 at the dome thermometer.
That is giving me a very even cook, and a nice skin.
It sounds to me like your using too much heat, so the skin is going too dark before your meat is done. You need to get a thermometer inside your cooking chamber to find out how hot it is in there. You need to be in the 300-350 range.
CD
