Cut out the backbone and split in between the breasts to get 2 halves. Brine and season as you would any other chicken and throw on the smoker. Make sure to get the breast and thigh to the required temps. Cook up both halves so you can have a choice of which one looks better. Plus then you have some chicken for lunch next week.
If this is your 2nd cookoff, I wouldn't worry about the extra category of dessert. Just concentrate on your meats.