It'd probably be easiest to just create your own winter board theme folder and then only drop in the music.app bundle with your icon changes. This will keep your changes temporary and not overwrite system files. I'm not sure, but you could probably swap out the png files in /Applications/Music.app but I wouldn't recommend that.
Okay please forgive my ignorance but I've never created a winterboard theme, I always just SSHed in and replaced the icon .pngs with alternate ones I found on deviantart etc. when I did it years ago (though I know with iOS changes that's not as simple now and directories are different etc.).
Could you please tell me where I should create the winterboard theme folder?
And then should I just copy the existing musicapp bundle out and make changes in Photoshop if I do it myself? Or are there any places where you can download alternative icon bundles just for a single icon? (I mean I know you can download entire pre-created themes from Cydia but thats the only icon I want to change so I don't want to do a whole theme).
I'm not looking for anything complex I just can't stand the iOS7 music icon.
Thank you SO much for your help!