ok, so aircon unit and a co2 kit in the cab.Again, I have to agree with soursmoker. You may be better off completely sealing things and supplementing co2.
I'm in Florida and it's literally hot as hell down here so really the only way we can grow indoors is with a sealed, cooled and co2'd room.
so i would need to design a air tight cab with no exhaust fan set up and the figure out how much co2 to release into the size of the cab?