Pork Butt - Can't seem to get meat's internal temp high enough. Using a WSM 18 1/2" and recipe from "Smoking Meat" by Jeff Phillips (pg 84). Should be a 10 hr smoke.. I'm at the 9th hour and internal temp (of the meat) is reading 171. The book calls for 205. I'm using the top rack in the grill, but can't imaging that would be the problem. Anyone have any suggestions, etc. May have to end up putting this sucker in the oven, but sure would like to know what I'm doing wrong. Thanks in advance.