How do I delete sounds and methods?

I imported a number of sounds into a world I was building and now the file size of the world is huge. I'd like to delete the sounds to reduce the filesize of the world. I was hoping I could avoid starting from scratch.

I navigate to the World's Detail Pane and locate the sound files as Sounds under the Details Tree. I see all of the sounds I've imported. If right-click on a sound file I see that I can rename it but that's all. How can I delete them? Is it possible perhaps to remove them directly from the world file (.a2w) without corrupting the file or is there a simpler solution?

I also can't delete object methods once I've created them, again in the object's details window, I only see the Rename option when I right click on the method. I guess I could just create a new instance of the object and copy all of the custom variables, methods and functions to the new instance minus the methods I want removed. Am I missing something? Is there an easier way?

Thanks!