Truckers with no APU-Unit & Can't Idle-Heads Up! Take a look and this may be for you to get some sleep.
ZERO BREEZE Mark 3 AC
Meet ZERO BREEZE Mark 3, the most powerful portable AC yet. With 5,280 BTU cooling power and weighing under 22 pounds, it’s perfect for spaces up to 150 square feet. Set your ideal temperature between 61°F and 88°F and enjoy unmatched climate control wherever you go.
Antonio
I have heard great things about these, and it has a battery and you can buy a couple of them if needed and also run it off an inverter of a certain size I'm sure. I would close that cab-curtain and make a window-mount for the exhaust-air to work better.
https://www.etsy.com/listing/1581036296/portable-ac-window-vent-for-freightliner