What was found
***CORROSION*** ON L/H OVERWING EXIT CUTOUT LOWER SILL WEB BETWEEN STA 627-638, LBL 64-70, WL 230 UPPER SURFACE VARIOUS SPOTS. REMOVED CORROSION ON LH OVERWING EXIT CUTOUT LOWER SILL WEB BETWEEN BS627-638, LBL64-70, WL230. DIMENSIONS OF DAMAGE REMOVAL AREAS FOUND TO BE 3EA AREAS 1" X 1", 1EA AREA 2" X 6" WITH A MAX MATERIAL REMOVED OF 0.048" DAMAGE FOUND TO BE OUT OF LIMITS PER SRM 51-10-02-0G-0 AND SRM 53-40-05-06-G. BOEING DWG# 144A8201, AND BOEING DWG# 144A8222. PERFORMED GOOD OPS CHECK OF M2177 LEFT CLOSEOUT PANEL HEATER