A bottle of water doesn’t cut it in 117 degrees. Especially if it’s in the jeep getting hot. If your core temperature gets up too high, you die. And really, they should have AC.
UPS, USPS, and others, they all buy special truck fleets, it would be reasonable to design special A/C for those open door trucks focused purely on the driver in between stops and it would also cool them if the heat was so bad that they needed to just sit in it for 15 or twenty minutes to get their body temp under control.
How about cold water?