Saw the beer can chicken episode on PBS this weekend. Best show so far in the series!
Couple of additional tips that may be helpful.
Add a little water to the foil drippings pan at the start of the cook. This will keep the drippings from burning. Doesn't need a lot. If you prefer use another liquid, such as apple juice instead of water. Throw in some of your rub, too.
At the end of the cook, save the drippings. Skim off some of the fat. Deglaze the pan for a gravy or sauce. Depending on your rub flavors, add complimentary flavors such as orange juice to make your sauce.
Another tip is to set your 'canned' chicken in the drip pan itself. Set that combo on the grate. Choose a small drip pan, such as a disposable pie pan. I've found the chicken to be more stable than when it's set directly on the grate. Mound your charcoal on either side under the pan. Then, put a few coals directly under the pan. That helps even out the temperature. Not too many, though. You don't want to burn the drippings.
If you have access to quail, you've gotta try the pineapply juice can. Those looked delicious!! Sure made me hungry watching those come off the grill.