Good luck Slow. That is a lot to stuff in a 12 inch. If you have a kettle style charcoal grill, you might consider Spatchcocking the bird and cook it indirect. To do that you cut the breast bone out and flatten the bird. Like a butterfly. You need to press down on it to break the back bone. Then the bird lays nice and flat. Start the coals and after they are ready move them to the outside and put the bird not directly over the coals. Some olive oil and salt and pepper the bird before tossing it on the grill and let it go. It will cook much faster then a whole or stuffed bird will.
Having cooked several both ways I think Woodbutcher is on beam. A Smokey Joe JR style charcoal grill with a big stainless steel mixing bowl filled with a bit of water under the bird and the charcoal as an outer ring makes a beautiful bird. What I missed by using the D.O. was that wonderful smoked taste and smell.
Well. good work Slow. Now you have something else to cook at the next gathering! If you keep practicing you will be able to do a Dutch Oven seminar too.