You could do an experiment too with things you think might work for you. Have your kit packed but then put some other items in your trunk and see how well they hold up. I noticed that Hooah bars have done okay for me so far as an extra food source. They get a little slimy after some time, and I haven't had them in 100 degree temps (not yet) but they are still quite edible.
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Ors, MAE, MT-BC
Memento mori
Vulnerant omnes, ultima necat (They all wound, the last kills)