Just my advice, you need only the carbon filter setup working the top of tent and blowing out from the top of tent going into your attic or where ever it runs to, to get rid of hot air and smell. But it all needs to stay at the top since heat rises. If you want to put AC into the tents then run a duct into the bottom of your tent but only a few inches inside the tent and secure it that way so it does not take up and room. Then you wont have any duct in the way at all. Thatll give you approximately 42" of height left to work with (and thats just an estimate idk how wide your exhaust fan is so im giving it 18") As long as you keep your plants under 2ft (from the ground not soil) which is doable with proper lst and the right strain choices then that will give you around 18" from light to top of canopy. (Might even have more space, again these are estimates of measurement but im exaggerating them so youll likely have more room than i am stating) Start heavy LST training and pick shorter genetics to keep your plants short and stout. Buy a migro aray 4+red. Bada boom bada bing. Good to go!