REWARDS - Respect, $20,000
The name alone should make people who have played GTA3 remember. Head to the airport and get on the jet. Take off and head to the yellow blip in the east. Once you reach it, you'll be in LIBERTY CITY! The guard says the party is invitation only, but CJ barges right in and dives behind a planter. Using the planter as cover, take out any guards on this floor, then move downstairs and take out the rest.
Follow the path and take out any and all of the guards that show up. Eventually, you'll be outside in the back where you'll find the last of the Forellis. Take them out and when the last one falls, CJ will be back on the jet. Fly back to the Las Venturas airport and land anywhere on the runway to finish the mission.