This mod adds Utsuho Reiuji's (Okuu's) 'Solar Sect of Mystic Wisdom ~ Nuclear Fusion' when you take out the apparatus with FacilityMeltdown.
I have seen there is a similar mod, but this one extends to 3 minutes since thats how we have our Meltdown timer set in our modpack (the default time should still work fine). Its also more compressed than the other mod i have seen. This mod also replaces the sound when the Apparatus is pulled.
Make sure that the music volume in the FacilityMeltdown config is set to 0, otherwise you will hear both the Okuu music and the default music from the Meltdown mod simultaneously.
If you find the music to be too loud or quiet, I recommend changing the master volume in the PizzaTowerEscapeMusic config to a value that you prefer.
Solar Sect of Mystic Wisdom ~ Nuclear Fusion - Touhou 11: Subterranean Animism