Optional video tutorial for installing SuperBLT, BeardLib, and mod_overrides mods: https://youtu.be/rin_sjSJIkg

After downloading the mod, use your .zip extractor of choice to move the mod's folder into your mod_overrides folder under "assets"

To select the track, head over to your main menu and go to:
Options > Sound > Custom Menu Tracks

And then you should be able to select the track in the menu