You put the smoker in the sheet pan, not on top of it. Push it to the back of the pan and that will leave several inches sticking out in front to catch drippings from mopping or moving meat in and out. It will also keep junk off the floor and table when, not if, as Gil said, you forget to use the drip pan that comes with your smoker.
I think what Dale is saying is, that he uses a pan with two inch sides that rests underneath his smoker on top of the casters so it acts as the outside catch pan instead of the one he was sent. He slides it in when cooking and out a bit to catch drippings when he opens the door. He says you could put foil in it too, if you wanted. Am I right Dale?
The outside pan doesn't preclude foiling the inside bottom of the unit(remember to poke the drain hole open.) It makes cleaning it a breeze.
Never heard of using a pan inside. Depending on your load, there might be more drainage than a pan inside could hold. Anyone else have a comment on that one?
Make more sense?
Hook