The outside handle won't open it iirc. We always had to bust the latch open from down the window hole with a screwdriver.
As soon as you get it open have super lock turned off.
The rear tail door window is easiest as it uses a gasket.
What has no doubt happened is the cruciform piece of pot metal that goes from the key to the door lock actuator has broken, thus the key just spins. Given this being most likely, once the vehicle is opened by turning the lock, the Superlock activation should deactivate because you are using the key (or the alarm thinks so) and you should be able to enter and start the truck.
I suspect you could drill out the key cylinder to access the door lock actuator as the mating part of the actuator is directly in line with the key hole. Thank you John for your suggestion as somehow, the idea had eluded me but when you suggested it, it became immediately obvious you have the right idea here. GENIUS!!!
Definitely have the Superlock function deactivated, I suggest everyone do so as the risk to the truck from a mal-functioning alarm is far worse than the risk of theft.
As for breaking a window, removing the rear door glass can be a challenge without breaking the glass
.
I find the left front door glass to be the easiest and least expensive to replace.
When breaking glass out, take a trash bag, place a hammer inside the trash bag, tape the bag to the window frame and use your trusty shop-vac to suck the bag into the hose, gran the hammer and break the glass. Most (note, most) of the glass will be sucked into the shop-vac rather than making a mess and leaving you with a lifetime worth of tiny bits of glass in the cabin.