Atlantean:
You can't do anything about what she is going to say or what is going to happen. If she likes you, she likes you, if not, then don't worry about it. Worrying about what is going to happen or what the consequences are will do no good. Just finish up this email business and tell her straight up (in person) that you like her and want to pursue a relationship that's more than just friends. If she is really a good friend, then even if she says "NO", she would still be your good friend.
This is really about you. If you can live with the fact that she doesn't like you beyond friends, and continue being friends with her after that, then you have nothing to worry about and are true friend to her. However, if once you find out that she doesn't like you, and you can't keep being friends with her, then there's probably no hope of keeping a friendship between you two.