If i'm being upfront I have never normally cooked a Beer Can Chicken on my smokers usually because Ilike to do them on the Weber Kettle. That's not say you can't, I think you will want to cook it above the usual temps for smoking.
If I were to do a BCC I would probably open all the vents, have no water in the pan and cook it quite quick. I like crispy skin on my BCC. I did do chicken halves for my inaugural smoke.
It's all about playing with your first few smokes, I know on reflection and looking at my photo's from my first smoke that I do so many things differently now. Does that mean what I did back then was wrong??? I would say no, we enjoyed the food, it fed my appetite to smoke more and I had a damn good dinner.
I would definitely keep a photo library going of your first few cooks. It make's interesting viewing in years to come.
Just uploading my first fire pics to photobucket for you to mooch through.
http://s280.photobucket.com/albums/kk17 ... st%20Fire/