Part of my family comes from Cascia and my great-grandfather, being a doctor, a socialist and (hence) a reknown atheist was once asked by the local authorities to visit the body of the Saint to see whether it was really incorrupted. The rationale behind the choice was that only an atheist would have been honest in describing what he would have found. And, in fact, the doctor reported that the body was incorrupted (at least, I suppose, if compared to its age). Did he convert to Catholicism after that? No. Did anyone become a stronger believer because of his fundings? Possibly, but only because they fit with what they believed already.
Let us suppose that someone finds an ancient body which, because of impredictable circumstances, has been incredibly well preserved. Will she think that this was the body of a saint? Most probably not, unless she has further evidences of it. She will rather look for "scientific" reasons, such as extreme coldness, lack of humidity, etc.
Similarly, why is it so important to know whether scientific evidences are found in favour or against the core points of one's faith? Jayarava addressed the topic of rebirth in a recent, interesting post. Unfortunately, comments are not allowed, perhaps because he received too many harsh answers. But why should readers overreact? Natural sciences speak about matter and can hence not really exclude ALL sort of continuity. Thus, if you think you have enough reasons to believe in rebirth, natural sciences will not make this belief unsound (conversely, if you want to believe that the earth has been created, say, 6000 years ago, you will have the problem of justifying why it has been created with fossils, etc.). Thus, what bothers one in reading that natural sciences do not support the belief in rebirth (nor in Heaven, etc.)? If one needs the support of natural sciences in order to believe in something, does not it mean that she is not really believing it? By contrast, natural scientists should avoid bold statements about the fact that they "proved" that rebirth, transubstantiation or miracles are impossible.
One might object that there must be consistency between what one believes as matter of fact and between what one believes because of faith. This is true, and the solution of similar conundrums is one of the reasons for the existence of theology. Theologians will, e.g., explain in which sense the two –seemingly contrasting– claims have to be understood.
What is really at stake when one looks for scientific evidences?
I already discussed this issue at length, especially with Aśvamitra and Vidya, see this post and this one, and the comments on them.