Good afternoon sir! How've you been? How was the butt?
You'll see all types of info here on this. You'll see arguments for and against most everything. For the first go-round, so that you minimize your opportunity to kill them, I do suggest that you foil. A little flame up, a little to much of this or too little of that and you've made tough ribs.
The way we do it (mind you, this is on our smoker, your results may be very different) is:
First, we remove the membrane from the baby backs (we dont spare).
Second, I marinade them over night, in guess what?: 1 part apple juice, 3 parts water, and a fractional part of worchestershire sauce
The next morning about the time I'm light the fire I take them out of the marinade and apply our rub.
The smoker usually comes up to temps in about an hour after we applied the rub. I put them on the smoker, at 250 degrees (a little higher wont hurt a thing). I spritz using apple juice and worchestershire once, at the 1 hour mark. I use hickory for smoke, and IMHO it can consume a rib after a while. As a result (to prevent too much smoke), we foil at the 1.5 hour mark and spritz heavily before sealing up the foil. They stay in foil for another 2.25 hours, for a total time of 3.75 hours. I take them off and allow them to rest, but no more than 2 hours, usually more like 1 hour. I apply the finishing sauce when it's extremely hot, and then only a very thin coat, just before serving.