Where is the thesis statement located in a position paper

In the Introduction passages to the paper.

Explanation:

A position paper is one i which the researcher argues for a specific position throughout the essay by presenting his evidence and countering previous claims.

This is why, the thesis statement must come at the beginning of the paper, usually after a paragraph or two introducing other ideas that the position of the author is in support with or disagrees with, so that the rest of the paper can be about the argument.