I built a 3/4 in plywood box 12in high and 2f 2in X 2f 11in. It has ceramic tile (scraps) on all sides and bottom (not top.) 2 socket fixture is mounted on back (short) wall. I have a modified Lower Hotwater heater thermo. about 3 inches from fixture and fan on opposite side. here is where i need help.... I am holding a great constant temp, but not even temp. If I deflect the direct heat/light will that work? Is HWH thermostat more sensitive mounted backwards? suggestions on evening temps? I am trying to stratigically place vent holes to pull air from back to front. suggestions?