i have la noire complete edition and want to install it to my rgh slim with fsd and it comes with four disc. is the 4th disc dlc only?? and if it is do i install the 4th disc thur NXE and will it work like that?

this is how i have it setup

HDD/games/LA noire/Disc 1/ (game files here)
HDD/games/LA noire/Disc 2/ (game files here)
HDD/games/LA noire/Disc 3/ (game files here)

and what do i do with the 4th disc? insatll the same way or thur NXE?

thanks