I've put alot of thought into how exactly you could store fuel for a BOV when the pumps may be empty SHTF. Well I've been looking into propane conversion kits for carbureted gas cars and trucks and they're fairly cheap ($800) and some kits allow you still run off gas.
Another good thing about propane is that it does not suffer from the same issues that other alternative fuels have such as ethanol and veggie oil not wanting to start a cold cold engine. Or ethanol destorying your gaskets.
After some research I'm strongly considering converting my 1994 F150 with a 300 I6 in it to carburetion and putting a propane kit on it.
And just on a side note for those who want to save money driving there older car or truck, propane is alot cheaper than gas at the pump. But is against the law to use because it's not taxed. So if you're about to get pulled over you may consider switching over to gas lol.