Here is mop I used on ribs and butts back before my first WSM when I was still using a log smoker.
Southern Sop:
2 C cider vinegar
1 C water
3 Tbsp black pepper
2Tbsp salt
1Tbsp Worcestershire sauce
1 Tbsp paprika
1 Tbsp cayenne (I used to go 1 tsp here since it was a bit hot for the family)
Heat it up and baste warm
Hope this helps. Again I haven't used it since my old log smoker, but it was a good all purpose for pork. Even used it on a couple of whole hogs!