Rack position?

I don't think it matters when it comes to smoke it might matter when it comes to temp..I keep my rack holders high but I keep the rack in the middle if I am doing butt,brisket and chickens.Ribs I put the rack at the highest because I hang them.I have had to use two or three racks at the same time due to volume of product and they all cooked evenly.

You might find that the bottom rack gets a bit warmer being close to the burner. When doing 3 racks of stuff like jerky, I switch the top & bottom half way thru. For 2 racks worth, I use the top & middle.

The fixture screwed into the back of the oven near the center is what holds the thermocouple and controls the heat. I have my best success if I load the food so it is above this. It gets a better reading on actual oven temperature, and I get more even cooking. If I am loading the oven completely full on all racks, I will rotate the top and bottom racks a little over halfway through cooking time. This gives me more even cooking on the whole load, and I do not have one piece of dried up meat from the bottom.