What was found
LEFT WING TRAILING EDGE UPPER COMPOSITE PANEL FWD OF LEFT AILERON IS BULGING, NUT PLATE CHANNEL SEEN FROM THE BOTTOM IS DISFIGURED POSSIBLY BY CORROSION - AA003. CLEANED AREA STR -Z-500 STR: LEFT WING TRAILING EDGE UPPER COMPOSITE PANEL FWD OF LEFT AILERON IS BULGING, NUT PLATE CHANNEL SEEN FROM THE BOTTOM IS DISFIGURED - IAW SOPM 20-30-03. INSTALLED NEW STIFFENER PN: UP-113N1184-3 ON LEFT WING TRAILING EDGE UPPER COMPOSITE PANEL FWD OF LEFT AILERON IAW B757-200 SRM 51-40-02-0G.