I would highly recommend getting a remote read thermometer like a Maverick. It will have 2 probes. One for the meat, and one for the grate temp.
They're one of the cheaper models but usually work quite well. Mine reads 4-6 degrees off, but in 99% of my cooks, that is insignificant. You can do 2 tests (ice water and boiling) to know what the accuracy is. Then just cook accordingly.
My smoker is on the deck of my 2nd floor condo, and it will read when I go get the mail (100' or so). And that's going thru 3 walls, a floor, and my covered parking spot. My desk is 2 walls and a brick fireplace away. Never had a dropped signal in 4 years of regular use (other than battery failure).
I learned in short order that I couldn't trust the lid thermometer or the erratic changes on the digital controller. Who wants to keep going outside every 15-20 minutes to check up on their smoker?