Even if you had the lights 10 feet above the box, shining into it, it will get hot. Think of a greenhouse outside- sun is millions of miles away. If you mount the fan deep in the box, it will be much quieter. I have a bunch of PC type fans, for several set ups, all mounted inside, blowing into 12"-24" long flexible ducts, through wall, etc- you can't hear anything unless you're right next to the outlet. Most of the noise is from vibration, not the airflow. Hanging the fan with o-rings/ HD rubberbands or such will help too.:jointsmile: