This mission is given by Tam Brodie.
"Jimmy? It's Tam. Remember how we used to box up at the Hill O'Tara? Well, the Chinese hold a fighting tournament every year called the Golden Fist. The main prize is 1000 bucks and a car. Should be a piece of piss for a big lad like you eh? It would be a real kick in the balls for Eddie Fu as well, which would make me very happy."
From the mission start drive the short distance to the arena, which is a circle of nine cars, then enter to start the tournament.
To win you'll have to fight against three different opponents, each one getting slightly tougher as you go. You will want to make sure your health is completely full before starting as it does not regenerate during a fight.
It's recommended that you've already played the main game and completed the fighting tutorial missions prior to this but if not, the on-screen display will tell you the basic moves, which are Light hit, Hard hit and Dodge. You will want to hold dodge until you're ready to strike your opponent and it's best to start off with light hits. Once your opponent has had enough, follow the on-screen prompts to finish him off.
When you beat the third and final opponent you will be transported next to the grand prize, the Waybar Hot Rod, and the mission will end. Enjoy your new car and you will even receive $1000.00 to go towards customizing it to your liking.