Try a 12 volt fan blowing on you one that has a timer would be best as once your asleep hopefully you’ll stay asleep, it will help somewhat blowing cold air on you buy be careful not to flatten truck batteries using one.
A damp towel underneath you can help as well or a damp flannel on your forehead. Or buy some pet cooling (unless they do human versions) mats and stick them under your sheet to lie on. They actually work quite well tbh and feel fairly cold.
Expensive options are a thermogel truck mattress so depends on if you could get your boss to pay for one or pay for it yourself to get a good night’s sleep.
I have the same sort of issue being at home and sleeping in the day on hot days but usually a fan is plenty adequate.