To use this mod you will need to download the Red dead radio mod
link: Red Dead Radio 0.9.9
Remembering that this will not replace the standard soundtrack of the game, you will only have an mp3 player within the game that you can play the songs from the first redemption.
To install you need to place the files inside the mod’s Radios at: Red Dead Redemption 2 \ Red Dead Radio
When you install you just need to press Q + R to open the Radio inside the game and select the radio and soundtrack you want to use.
Remembering that I didn’t make the mod I just separated the soundtrack from rdr1 all the work was done by kostas96b.
U can find the rdr undead nightmare and red dead revolver soundtrack here:
Red Dead Redemption Undead Nightmare SoundTrack
Red Dead Revolver soundtrack
Credits:
RedMaxBR