[REQUEST] Pokémon Yellow - Battle Music Modifier

[Ixkli21]

I'm sure you've seen this code before:

01025BD0

It's for Pokémon Yellow, quite obviously. What it does is change the battle music of ANY battle (Wild, Safari, Old Man, Gym Leader, E4, etc.) into the Gym Leader's Battle theme. However, all it does is just play that theme, no matter what you modify the "02" into, e.g. "02" --> "C7", which is the index for Cerulean City's theme.

Here is my question: is it a remote possibility to make a Battle Music modifier that changes the Battle Music into playing the Cerulean City theme or Cinnabar Island theme? I'll provide a .SAV, if needed. https://www.mediafire.com/?xr6auta5le3tk5b