1 week veg time tops. 6" pots. SOG. Whichever light you can get in there and air-cool. 600 should be ample for that space; if you go higher, consider adding CO2. I recommend a 4x4 table if you can get one in there- the 40gal res will do it fine and it's a better size for a large light. Add ventilation- use one fan to cool the light and the other to vent the room. Or try venting the room THROUGH the air cooled hood. If it still runs hot, add CO2 (read the 'sealed room' thread) or another exhaust.