i never baste ribs on the WSM. i used to spray with apple juice every hour, but after not spraying once i could tell no difference. every time you take the lid off you are adding more time to the cook as well.
I have yet to make a good rib, so I really changed it up today. I did not marinate the meat overnight, just sprinkled the rub on an hour before. I used only 5 small chunks of wood, and I am not going to crack the lid till the 4 hour mark.