This is a simple NO UMD FiX by LightForce:
1) Extract Naruto_Nultimate_Portable_JPN_PSP-Caravan to a folder on your PC using iSOBuster or similar utility.
2) From your original PSP_GAME folder move ICON0.PNG, PARAM.SFO, PIC1.PNG, and SND0.AT3 to the narutonp folder from this pack.
3) Next, from your original PSP_GAME\USRDIR folder move both the movie and sound folders (including all files in them) over to the narutonp\USRDIR folder from this pack.
4) Now, from your original PSP_GAME\USRDIR folder move both the naruto.dat and naruto.idx files to the narutonp\USRDIR folder from this pack.
NOTE: Do NOT move/use the modules folder from your original PSP_GAME\USRDIR folder as this FiX already contains the correct modules folder in order to have battle sound.
5) Now follow the instructions as normal from the included NFO file:
Put the 3 folders to memstick and start runumd ....
Now boot using RunUMD.
NOTE: Although this is labeled a "NO UMD" release, that just means you don't need the actual NNP UMD in the drive to play the game, however, you will need a UMD in the drive to run it (any UMD game should work).