With these 100+ temperatures we are having the ambulance gets hot during the day, especially since the inverter makes heat and the fridge/freezer makes heat that gets trapped inside when the truck is locked. So I bought a 12 volt radiator fan and I'm installing it on the small door where the O2 bottle used to go. It's going to be on a reverse polarity switch so it can suck air out or blow air in. The door is so small there is no way to rob anything from the truck. So while we are parked the door can be open with the fan running. It can suck hot air out or blow cool air in. The O2 door closed. The O2 door opened with the new fan. When I get back to Oklahoma I'll build a proper shroud for it. It works for now.