First finish the quest chain to phase out booty bay, more info on wowhead's guide to bloodsail admiral then stand between Rickle Goldgrubber and Viznik Goldgrubber in the bank, they both each gives 30 rep from the phased out booty bay with a respawn time of 1:50ish and Privateer Bloads who is next to them gives 6 rep with a less spawn time of 1:30ish. Thats around 66 rep in 2 mins which is 1980/h. you can use keyspam to spam any aoe spell every second, they will die 1-2 shots. Just one night of botting can get you the achieve and title. Others are unlikely to find you since your in a phased out booty bay and no risk of getting reported. You do not have to be 85 to do this.
Have fun.
Edit: I went from 33k hated to honored in 8 hours while sleeping.