So Im smoking 12 lbs of pork shoulder saturday (two 6lb cuts). Want to rest for 2 hours. I was thinking of putting it in the smoker at 5am so it will be ready for consumption for a party at 5pm. Also will be tossing about 3lbs of ribs in when I foil the pork at 50% (right around noon). Does this sound like a good plan to you guys? I figured that by adding the ribs when I foil the meat I can add more chips without over smoking the shoulder
Well you don't really need to worry that much about over-smoking the shoulder. Meat doesn't take smoke as easily after the bark has formed, and because shoulder has a smaller surface area / mass ratio than something like ribs, it's much harder to "over-smoke" it anyway.
How does your smoker usually respond to pork butt at your intended temp? Generally I assume about 1.5 hour/pound with pork, and I don't foil. (Foiling can speed it up, especially if you foil right around the stall). So two 6# butts would take me maybe 9 hours, since I don't foil.
If it were me and I were shooting for 5 PM, I'd probably throw them in slightly later, like 6-7 AM. And if I was planning on foiling, probably closer to 7-8 AM. But that's just how my smoker responds. If yours generally takes longer, work with the schedule you're used to...