thats the temps @ 50%?
Whoa!
Well it aint a total waste, Keep that fan filter combo just for that, and your gonna need to buy an additional fan / reflector to deal with this heat and to be able to run that to full power.
But for now you can get em in and not worry about death LOL.
That fan / filter combo will work perfect for a exhaust for the whole cab. That way you wont be blowing stinky air out anyways. - If you do get a cool tube to fit then that should have to be filtered. Also I would work add another intake, additional to that passive one, Forcing fresh cool air in.\
My tent I just check is running at 80 degrees with it open, I just closed it full and switched my fans around and put them on medium, Gonna see how high it gets.
You might have to open your cab up for a few hours everyday no matter what you do, LOL unless you have 1000's to dish out on cooling
After relooking , add a fan to your intake forcing air in, and you should be good to run at 50% - Then later get that cool tube, cut it down to fit or pre cut holes in your cab and slide one end in and then push it up and slide the other end in, leaving it with the ends sticking out and hook up your vent tubes and such outside...You would need to seal the cooltube in for light leaks but that would be badass!