What was found
DURING C-CHECK, FOUND FUSELAGE SKIN BELOW FREON EXHAUST DOOR HAS WORKING FASTENERS, LT SIDE. REMOVED INTERCOSTAL, FABRICATED NEW INTERCOSTAL, CLEANED CORROSION IN AREA, FOUND WITHIN LIMITS. TREATED AND PRIMED AREA AND INTERCOSTAL IAW SRM 51-1-8. INSTALLED REPAIR IAW SRM 51-1-8, SRM 53-3-2, SRM 51-1-21, AND SRM 51-1-20D. REF: OPERATOR CONTROL NR 0248.