How do you measure your temps (and where) and what do you use to do so? (analog thermometer, digital with probe, temp gun)

Also why side mounted, you do realize that it is very inefficient unless you have a heated room even than it's not the most efficient way to do it. It's pretty simple heat travels up therefore it make more sense to place the UTH at the bottom as you will suffer heat loss by placing a UTH on the side.