Right, so on the previously mentioned trip, my father started out with a working alternator, it failed, then he depleted the significant reserve of battery he had (the truck has two car batteries in it) and eventually was running with little or no electricity (I say little because maybe the alternator was running at some diminished capacity, but I do not know). Frankly, despite the fact that diesels don't in theory need glow plugs runnings, etc, I figured it wouldn't run w/o the computer system operating and I thought the truck had electric fuel injectors, but I guess I was wrong about both. Don't misunderstand, it ran terribly, but it ran. He was actually towing a boat, so it ran well enough to tow a boat to his destination at an extremely reduced speed.

I'd say perhaps the best BOV solution if you're THAT worried about EMP would be an old small diesel w/mechanical fuel injections and a standard transmission. You could, in theory, pop start this, but due to the higher compression in a diesel it'll be harder than w/a gas automobile.