Does he play 5-3N-2 or 5-3W-2? How big is the difference in quality?
5-3N-2:
I would field more MCs. 3N-5-2 or 3N-4-1-2 would be my formations of choice.
Attack him over the wing.
5-3W-2:
I would try 3N-4-1-2 and attack through the center (normal mentality). If he gets too much power over the wing, set blue arrows on your wingers.