smoking baked beans at tail end of pork butt smoke, few questions

Going to a family bbq this weekend, planning on bringing some pulled pork and dutch's wicked baked beans.  I planned on doing the beans in the last few hours of the pork butt smoke, but I also remember reading a while back that you should stop adding smoke at a certain point for the pork, and that 'over smoking' could start to dry the meat out.  I'm sure it wouldn't be too bad unless excessive, but I want to keep it as moist as possible.

Anyone see any problem with adding wood for the beans a few hours toward the end of the smoke, or should it be fine?  I don't foil my butts (at least not for now since I like a crisier bark, but may give it a shot since so many people seem to advocate it!), so I thought I would put the beans under the butt and catch some of the drippings too.  Shouldn't be any problems with that since the butt is pretty much cooked through at that point right?

Edit: sorry one more question- I see some people are fans of wrapping the butt in plastic after putting on the rub and leaving it in the fridge for a while or overnight.  What does this really do?  Any major arguments for/against it?  I've only done a few but I just prep mine immediately before throwing it on.  I thought having a salty rub wrapped up overnight might have a slight curing effect.   Thanks