Make sure to have OpenIV and then make sure to use the "Edit Mode".

After that, Open the mods folder, go to mods>update>x64>dlcpacks>polbuffalosx>dlc.rpf>x64>levels>gta5>vehicles>vehicles.rpf and open "polbuffalosx.ytd"

MAKE SURE TO HAVE THE BRAVADO BUFFALO SX INTERCEPTOR MADE BY L'KID INSTALLED.

L'KID's Bravado Buffalo SX Interceptor: https://www.gta5-mods.com/vehicles/bravado-buffalo-sx-interceptor-add-on-sounds