I re-arranged things and put in pallet racks this weekend. The reznor is mounted on the ceiling. The 42 inch pallet racks come about 4" away at their closest, then since the reznor is angled diagonally it fades to about a foot away. My number one concern of course is fire, do things in back of the heater get hot??? Second concern is airflow, I obviously will be leaving some good space there on the racks, not packing things tight right there at all.
here's a pic.....
here's a pic.....