When I did my fixed probe install I took the back off removed ALL of the insulation, then removed the door pins and took the door off, marked the spot inside as per Tony's post, I then laid the smoker on it's back so I was looking directly into it this works great as you will need a good bit of pressure to get through that stainless steal, it also helps to drill a smaller hole first, the whole process took maybe one hour from start to finish, and if you don't have good sharp bits go buy a couple you'll be very glad you did. Also if you don't want to do an auto tune you can just copy some of the other parameters used by others with the same smoker, that's what I did and it performs awesome, did 4 racks ribs yesterday, 235 for 5 hours, no peak, went and did a few errands came back to perfect ribs the Auber holding exactly 235......unreal still amazed by that thing.