First off, this deity has to be defined. What exactly is meant by the word "god"? If we are talking about the Abrahamic god, then I'm a 10, this creature, as envisioned by the faithful (of whatever stripe) most certainly does not exist.

If we are talking about any of the gods that the human race has invented over the years, then again, I'm a 10. Non of them existed.

Could their be some sort of deist "thing" outside of the universe, that has no interaction with the universe? By definition, this "thing" cannot be tested by anything in the universe so it is impossible to say either way. That would make me a 3.5 for this "thing". Do I think that this "thing" exists? No, I do not but because I cannot prove it one way or the other, I'm a 6.9 on this.

What evidence could change my opinion? Having been at the Dawkins/Grayling conversation in Oxford last year, I have to agree that there is nothing that would actually be good enough to prove to me that any god exists.

I live my life as a 7.