You only have to kill two for the quest and the respawn rates are very quick.
Steps[]
Sergeant Daimyo sends you to gate to Longshadow Alley in North Freeport to eliminate street toughs at ( -56, -20, -325 ) Copy/waypoint -56, -20, -325 and ( -101, -33, -329 ) Copy/waypoint -101, -33, -329