It's tough to do one. I generally will let a loin take smoke for 60 to 90 minutes (depending on the meat, heat, smoke). After that, I will pan it up and cover it. There is usually enough of a fat cap to keep it moist in the pan if you put the fat on the top side. I take mine to 170, but you could probably take them higher without much drying out taking place. That's only if your foil is sealing well with the pan.
Many times it will fall apart when I am trying to slice it. When that happens, it becomes pulled loin. If you think it dried out too much prior to panning, try pouring some zesty Italian dressing over it once it's in the pan. It will help to moisten it back up and give some added flavor. Check out my Pork-U-Pine link and leave out the hot link.