If you seriously want a storyline then here goes... God was always cast as a *ick! In the end Jack assumed God's powers and restored the world to it's pre-existing cesspool lol. Fast forward ??? years and Jack finds out that being God isn't as easy as it sounds. He's disenfranchised and has lost his way. Over the past ??? years he's created alternate universes some of which are complete failures including Earth # xx. He brings back the Winchesters along with their progeny to help him find his way and bring all created universes back to benevolance because Jack can't be a *ick like his predecessor. Jack sets loose the Winchesters and their progeny into the multiverse to restore beauty and balance. The classic car has multiverse and time travel capabilities to get the job done! Endless possibilities there!