Let me tell you a bit about beer butt chicken (a/k/a beer can chicken a/k/a chicken on the throne)
Ever make beer butt chicken on the grill? I tried it for the first time a couple of weekends ago and it was the best BBQ I've ever made. Use a 4 LB bird. Season it inside and out with your favorite rub. Drain half a can of beer. Pour some seasoning in the remaining 1/2 can. Stick the can up the chicken's butt. Stand the can up on the grill (note that you use indirect heat with a drip pan under the chicken) and use the 2 legs as to help stand the bird up. (or use this rack and don't worrry about keeping it standing). Bend the wings behind the bird's back (so they don't dry out, NOT to make the chicken say "uncle.")
After 1.25 to 1.5 hours of high indirect heat, the bird will be done. The skin comes our crispy, the meat stays juicy (yes, even the breasts!) Not only does the beer keep the meat moist, by introducing steam into the bird while it's cooking, but the beer and seasonings in the beer (I used Old Bay Seasoning) flavors it. I hear it's even better if you cook it in a smoker with some wood chips. BTW... for a rub, I used Montreal Steak Seasoning, but you can use your favorite rub.
Two birds will fit over the aluminum roasting pan that you use a a drip pan and don't take any more time to cook than one does. A single 4 LB bird will only go so far. If you use a larger bird, it will take longer. You can use a 16 oz can in a larger chicken.
here is a link to help you cook it