Temp. Control in Attic Crawlspace

I'm short on room, and the attic crawlspace is the only way to go.

Only problem is that its probably going to get up to 85-90 degrees up there during the day.

I'm definitely going to be building a growbox... and plan on having like 4 plants up there so probably a 3x3x6 setup
fluoros shouldn't create too much heat, and i have access to outside air so what can i do?

Ice in the growroom or around the intake fans?

turn your light on 10pm to 10am it will help when the days go in the high 90's