Most likely, any vehicle with an alternator is done. You may get 20 miles or so on the battery, but the diodes and regulator in the alternator are solid state, and an emp will pretty much toast them as well as the electronic ignition, a fuel injection controller, and there's even a good chance it will fry the ignition coil! A good emp proof rig would most likely run on diesel with mechanical injector system and as little electrical as possible. Not very state of the art, but fairly bulletproof when kept to close tolerances.
The rest sounds like a survivalist's dream come true.
As far as aliens go, find someone with a head cold and have them sneeze or cough on the bad guys.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)