I am not able to use "comment" yet, please take this answer as a comment.
From your question, it seems you look at Neshama and Body 2 different "things" or objects. Yet, my understanding to Judaism, all is ONE. Adonai Echad. Could it possible body and spirit (besides, there is a mind as human being) is one, not two.
If there are 2, it means Hashem puts a Neshama into a body which is similar with your question: Neshama chooses the body.
If they are ONE, could it possible the quality of Neshama makes and forms the body? So, we say we can tell one from one's eyes, since eyes are the window of soul.?
Just a comment.