I've been thrown the task of cooking 100 lbs of pork loin for a lunch tomorrow.  There's a large oven available - standard and convection sides or a very large pit.  I'm leaning towards the pit, but I don't want the meat to come out dry.  No time to brine.  How long would it take on the pit; I can cook at a high temp. I'm thinking just under 2 hours at 275 -300?  Any suggestions on rub?