Filter, fan, and hood cooling question

I want to cool my light, and exhaust the filtered air under the house, but im wondering how to set them up?

A: Push the air through filter at the exhaust side, with the hood as the intake and the fan in the middle?

B: Filter as intake, through the hood, and then fan last

C: fan pushing through the hood, and to the filter?

What do you think is the best option, its a 4x4 closet with a 600hps?
ill be using 6 inch duct and probably a can fan, not sure yet about the filter

A. is the best bet as pulling air through the hood seems to cool it the best, i notice that the hood itself stays cooler because there is a vacume and the hot air is not pushing against the hood trying to get out....if that makes any sense

B if your intention is to have fresh air coming in, yes i too have found that sucking the hot air out of the hood cools it better,but i wouldnt want to submit my fan to those high temps, when i tried this i could have cooked an egg on the fan

Ok, I ran the 600 all night with the closet door open, and a small stereo cooling fan rigged in the fitting, and the room stayed below 84. im stoked. Anyways, ill be bringing fresh air in via another fan, but i want to make sure im not exhausting any smell.

So I guess the best thing to do would be Fan in room, blowing air into the reflector via 6 in duct, and then out the other side of the reflector, more ducting, out side, and finally the filter?