The thing is, everyone has individual "clock".
If you find that you can naturally fall asleep at 3AM, you will never be happy in 9-5 (unless it is in another time zone).
There are some schools that claim you can shift it, by ensuring you wake up at the same time no matter what and you will gradually go to sleep earlier to get that 5-7 hours.
But it's a misery.
It's much better to talk to employer and ask for individual hours and accept you are 3AM person. No more snoozing and happier life.