You said it, there is a wide variety of approaches taken by rehabs. I would suggest you phone and speak with someone at ones you are interested in. There are rehabs that are totally A.A. focused, there are cognitive/behavioural approaches, purely medical, and all manner of mixed approaches.
The question I would suggest you ask yourself is why you would prefer the day program approach as to the residential one. Again, explore a bunch of them and get a feeling from the people you speak to on the phone. They are very supportive and will answer your questions happily. That would be my advice.