My advice, even though you made up your mind, ask her. Being unsure about a friend that is a girl is possibly the worst feeling, having that hanging over your head, more than that it can get confusing. If you try running with that you can make a mess out of trying to just be friends. I suggest go for it, and honestly if you guys don't work out and she is as cool as you think. You will be able to be friends, I have been in that situation and we came out of it as friends. You just got to learn its got to be mutual no matter how you feel.
LOL at Kevin's video.