yarn mane question

I've got a -mostly- finished head, that I'd like to take a crack at fixing, the biggest problem being I screwed up on furring it and the back of the head is so small now it's almost impossible to wear.

So, my question is -- I want to remove the entire back of the head, but I glued it down to the balacava pretty well ...and well...I'm afraid of doing a lot of damage trying to remove it. Any tips how to most safely go about this and be able to preserve the balacava underneath? (FIXED!)

Also, thinking about adding a frayed yarn mane to the back of the head (think Cats wigs) and one thing I'm curious about is I've read some people hairspray their yarn "hair" I was wondering if anyone has experience in that department, and would love people's opinions. I know yarn (especially frayed) has a tendency to go FOOF (but I really love how it looks and I feel comfortable working with it) and was wondering how well hairspray works in keeping it under control. I'd also like to know is one application all you need, or would I need to use it every once in a while? Also, would the yarn to be safe to brush afterwords or would it be all sticky? Lastly, and brands of hairspray should I be using/staying away from?

Oh, I lied. One more thing. Thinking about putting small fake flowers and maybe beads and stuff in her "hair" and wondering should I just use hot glue or?

Thanks guys!