i was a pioneer and a servant in the late 60's. we all lived and breathed 1975. i became apostate before 75---so waited with baited breath to see if i was right lol'
as for your question about 6000 years--its easy enough :---from now--back to christ---2000 years orgive or take a few. from christ back to adam--using the genealogy in the gospels---around 4000 years.
---that asumes adam isnt simply a myth.
then--to spice it up a bit--tack on christs milennial reign----and---wait for it----decide a creative day is 7000 years long--then you have the perfect recipe to sell a ton of 100% pure bullshit to a group of sad cases who want all their neighbours dead so they can steal their houses.