It wouldn't happen. 1 def and 1 pray would mean you would have to stay on floors 20 and below, other wise you would get your ass whooped. So probably like 3 months 24/7.
Well it took me 5-6 months doing a couple floors a day on a lvl 138, sooo i would guess unless you get to piggyback on pro teams like pure kq pax, I see no way for you to do it w/o it taking a year.