My first fridge to smoker project

New here and looking for advice on my first try at converting a commercial fridge into an upright wood smoker. A friend in the restaurant biz is giving me a single door, stainless steel fridge from one of his locations. I'm ripping the plastic interior and existing insulation out this week and removing the compressor/mechanical stuff from the top of the unit. Once I have it down to the shell, I need to figure out where to put all the necessary elements. I plan on making this a wood fired smoker and really need some tips on temp probe/gauges type, optimal placement, insulation (Ruxol seems to be the choice from what I read here), firebox design/placement (at the bottom of the unit or connected on the side?) and should I include a gas assist for some reason?
I've really only smoked on my grill and used a probe that connected via Bluetooth to my iPhone, so any pro tips/advice I can get here could make my summer a smokin' success!:sausage: