I bought a picnic shoulder because it was super cheap. I usually cook boston butts for pulled pork and find they take 2-2 1/4 hours per pound consistently at 220 grid temp. I used this "rule of thumb" for the picnic and the thing is at 183 now(9:24 am). If I double wrap in heavy foil and throw in some newspaper, will it hold until 3:30-4:00 pm? Thanks.