I am in the heart of Pork BBQ country and, I don't have a smoker. I know that a Crock Pot isn't going to produce a product that is on the same level as a smoker, but we do what we must when there's a good sale on a pork shoulder (butt). Because of the amount of fat in a shoulder, you don't have to worry about it drying out. Just put the fattier side face down. It helps to flip it before the side on the bottom is fall-apart tender. I do salt, pepper, granulated garlic, a pinch of red pepper flakes, and a little splash of apple cider vinegar and let it go until it's ready (except for 1 flip, halfway through.) I guess you could add a small amount of liquid smoke, but I've never used it. Also, when it's done, strain the liquid and refrigerate overnight. The result will be a layer of beautiful, white pork fat and some great pork Jell-O that will make a great pazole!
