They are across from the gym... if they give you trouble... if they make excuses... HURT them.Senor Mordino

Collect tribute from the Corsican Brothers is a quest in Fallout 2.

Quick walkthrough

Side Quest: Collect tribute from the Corsican Brothers
Complete Deliver Big Jesus's package to Ramirez at the Stables quest.
Go to Golden Globes Studio.
Complete Become a Prizefighter quest. (optional)
Intimidate the Corsican Brothers.
Return to Big Jesus Mordino.
Reward: 500 XP, $100
Next quest: Assassinate Boss Salvatore for Big Jesus Mordino

Detailed walkthrough

Big Jesus Mordino has asked the Chosen One to collect tribute from the Golden Globes porn studio. The Chosen One must enter the "lively" film studio and tell whichever one of the Corsican Brothers is in the office that the Chosen One is from Senor Mordino. The Corsican brother will get fairly nervous and, with a shaky hand, give the Chosen One $200, half of which will be his reward for reporting back a successful mission. If one is a Prizefighter he will gladly give them $250 instead. Big Jesus Mordino later explains that he had already received their payment for the month.