To download and install the ModSource Better Music Mod released by Caveman:

Step one

Have a file extraction program such and winzip that is capable of opening multi-volume zip files.  Most programs are capable of this.

Step two

Download both files, the ZIP file and the Z01 file and save them both in the same place.

Step three

Open the ZIP file.  Ignore the Z01 file your extraction program will access this file behind the scenes.

Step four

Referencing the included readme install the mod and ENJOY!