If it rolls to the right with right rudder, you have too much (effective) dihedral. Since decreasing the dihedral on the lower wing will decrease your wing tip to ground distance (more likely to tear up the tips on a bad landing) I'd suggest changing the top wing. Another reason for adjusting the top wing is that it is the one causing the coupling. It's larger than the bottom wing and above the center line. Don Lowe showed a picture of an EZ Citabria several years back where the owner actually turned the wing upside down, since it was symetrical, and the resultant anhedral resolved almost all of the roll couple. But, I'd take care of the rear of the fuse first as it could very well change the roll coupling (if the tail is twisting) and give you a better feel of how much to change the wing.

Keep working on it! Trimming a pattern plane is one of those processes that can take a while, but well worth the efforts once you get everything dialed in.

John