One minor modification to my cab. I noticed the humidity getting as low as 35%. This is probably due to the extreme ventilation my box possesses. Therefore, I am using a home humidifier that actually blows cool air and it sits just out side my cab with it's air blowing towards the passive intake opening (from the outside).
This addresses a couple issues. First, it raises the humidity level in the cab from 35% (because of the wind tunnel inside my box) to 41% and it cools better. I am actually seeing temps a degree or so cooler in my box over the outside ambient temperature.
Only downside is filling the water reservoir for the humidifier. I have to say, it works quite well though.
I may get so,me pics up tomorrow. I'll remove the domes tonight. Two of my plants are growing nicely, based on what I can tell (and thanks for the advice from Gumball)
BTW my struggling plant it starting to show signs of life again.