I have done it both ways, and I think you get better results when the meat is in a pan. I also use the pan juices to baste the butt while its smoking. The pan juices will take on a lot of smoke & when you mix them in with the PP it adds to the flavor. After a short rest (30 minutes), I pull the pork by hand, (we like big chunks of meat & I can take out any fat I see) right in the pan I smoked it in with the pan juice & put it in another pan, along with a finishing sauce I think you get a better product than just putting the butt on a grate with a pan underneath it.
Here is the finishing sauce that I & a lot of us use, and Chef Jimmy J has a good one too.
SoFlaQ’uers finishing sauce
1 Cup Cider Vinegar
2 Tablespoons Brown Sugar
1 Teaspoon Tony Chachere's Cajun Seasoning
1 Teaspoon Course Black Pepper
1 Teaspoon Red Pepper Flakes
Warm the Vinegar up enough so that it dissolves the Sugar well. Then add the remaining ingredients.
I use it in one of those clear Ketchup bottles you can get from Wally World for about $0.99. Snip a little bit larger hole out of the spout with a pair of scissors. Once all your ingredients are mixed together, put your finger over the top, and shake vigorously.
Randomly squirt this over warm freshly pulled Pork, then kind of mix it up with gloved hands. This adds very little heat (despite the Red Pepper) and mellows out the stronger, gamier parts of the Shoulder. The Vinegar also helps break it down even more for some REAL juicy pork.
Personally, I eat it just like that, but your guests can add whatever "Q sauce they prefer once it's on their plates or bun!
Good luck & take some photo's!
Al