Suggestion. In the mission Just Business and/or reuniting the families, you will get to sit as passenger and shoot like that. Now, I suggest that in MTA:SA we can actually do the same thing, getting into a car as passenger with a driver, and shooting stuff along the way or on your tail. I know this is like not in single player GTA that you cant enter as passenger, and shoot in that car, so i dont know how hard doing this is gonna be, but take note its a suggestion.