You need to flesh out your idea here. What depth would be added by disability? How would it add to the anti-war message in the monologue? Are you a professional actor or a drama student? The subject matter is already pretty heavy and adding a life-altering disability like stuttering needs seriousness and professionism. I say do the monologue straight without the bells and whistles of a stutter. The blocks and secondary charactertics are hard to mimic and are, imo, the most impacting, and painful, part of stuttering. Why mix these two human horrors?