Respect for the homie Pac
NOTE: This features ONLY a sample loop, there are no vocals.

1st, startup OpenIV (if you don't have it I suggest you get it) and go to this location:
GTA V - Mods - x64 - audio - sfx - PROLOGUE.rpf

2nd, drag and drop "tdloadingmusic.oac" into "PROLOGUE.rpf"

and BANG! you're sweet.

Don't upload on other sites without permission