You can search around on some of the pulled pork threads and get plenty of ideas on how to finish cooking it early and keep it warm until dinner. The preferred method around here seems to be placing it in a cooler wrapped in towels to keep it warm (which I have done with great success). On a 3lb butt I would figure 6 hours of cook time to be on the safe side then 1 hour of resting time. That way you have some time to spare. If it seems like it is stalling for too long around 160 you can wrap it in foil to help it along.I plan to pull it. I ready that 200-205 was the magic number but also read it will stall so I just wanted to make sure its done in time for dinner thats all. Im in nebraska and have a smoke hollow electric smoker with a mailbox mod if that helps