With the bottom skins off, deburred the main spar where drilled. Temporarily cleco'd top outboard skin. Positioned and drilled the stiffeners I pre-cut when doing bottom. Also cut outboard most stiffener as it differed from bottom. Deburred stiffeners and stiffener holes, applied Cortec, and riveted top stiffeners using A4. Removed top skin and did more debur of inside surface.