Bob,
The beauty of this hobby is that lots of layouts fly no matter what. And we can then see how they fly and trim 'em to fly better. Well, "better" if in fact they don't fly good enough.
Changing an ARF or even a kit airplane's AOI's is very seldom needed but almost always a real effort.
Incidence- Wing: +2°
Stabilizer: +3° with the aft deck base at 0°
If the wing has a cambered profile (Cub models almost always have cambered airfoils), then the line drawn along the flat part of the bottom of that airfoil is probably not the AOI line. That +2degrees is probably a line that goes from the middle of the LE to the middle of the TE. And that's not a horizontal line. These details always make this discussion harder.