Contrary to your comments, the wing fuselage junction of a Grumman actually includes a dedicated aerodynamic, non metallic fairing/fillet with a compound radius along the root and trailing edge to smooth airflow. It also reduces the junction of the wing and fuselage to roughly 90 degrees on the upper surface, somewhat mitigating the interference effect of the dihedral angle, as well as providing a level surface for the wing walk area. The fillet is possible, in part, because the wing flaps are positioned further outboard from the fuselage than with some other popular aircraft. With respect, your description in this area is not accurate.