Mounting your cooler in the "Nostril" is an easy little job and the cable should also be easy to route into the area.
The inside the cab locations can be tedious as you have to cut and splice the cable to get it inside without cutting a huge hole in the firewall.

Out of the heat and into the cool air is the ticket.
I would also recommend carrying a spare PMD even if its only a known good used one.
If your setup is done right you can even mount two on the same cooler and in the event of a failure you just swap the wires and off you go. I have also seen folks keep one on a manifold mount cooler tucked away and its a snap even at night in nasty weather to unplug the cable and plug in the extra and just lay the cooler on the manifold. (This would get you home)

Glad you are on top of it.

Best
Robyn