I butcher 3-4 pound yardbirds to halves, cutting the backbone completely out and sometimes the keel bone in the breast too. This makes 2 mirror half chickens. I brine with a basic 4 Tbs sugar, 2 Tbs salt to 1 cup water mix. I put seasoned (with chicken seasoning) butter slices on the breast under the skin. Smoke them for 2 hours, then cover in pan in sauce & chicken broth bone down for 30-45 minutes. Glaze then set the sauce 15 minutes, then turn in.
I don't cook many IBCA contests, but the technique above got 10th at the Cowtown Speedway in 2009. I was the only foreign (non-Texas) team there!