All credit goes to ZUN, the creator of the Touhou Project.
Tracks are from Touhou 12.8 Great Fairy Wars.

Requires SuperBLT and Beardlib, you know, the standard for adding custom music.
Drop in mod_overrides, so that your file path is exactly "\PAYDAY 2\assets\mod_overrides\great fairy wars&lt;files>", where <files> are the loc and sounds folders and main.xml. Having an extra folder in this path due to unzipping the files is the most common mistake made when installing mods.

Stealth track: Stage 2, Year Round Absorbed Curiosity

Buildup / Anticipation: Stage 3, A Midnight Fairy Dance

Control: Stage 1, The Refrain of the Lovely Great War

Assault: Extra stage theme, Loose Rain