Let's see.
Gaara (who has Shukaku within him after the war I Assume) Can Release him while still being himself as seen in part one. He can release Shukaku, who can match Mecha Naruto in Size and Brute Force, while Gaara restrains it. Kurotsuchi can further restrain him using Quicklime, while Chojuro and Darui Batter it with a Water Dragon Black Panther Combo jutsu. Gaara and Shukaku crush the Mecha.
As far the small version it gets rekt. Gaara and Shukaku should be able to catch it with Sand or at least slow it and Kurotsuchi can make him extremely heavy where it cannot move.