Sanded out/scotch brited scratches on the insides of the HS skins. Scotch brited the lines of rivet holes to roughen the surface. Wiped the skins w/denatured alcohol, then MEK. Sprayed the rivet lines and blended-out scratches with AFS primer/sealer...did not try to prime the entire inside of the skin. Sprayed the remaining HS ribs.