What was found
B757-53-3-0526 AFT CARGO INTERCOSTAL INBD SIDE BETWEEN BS 1420 & BS 1440 RBL 10 HAS CORROSION SEVERAL PLACES. REMOVED INTERCOSTAL GAIN ACCESS TO CORROSION, REMOVED CORROSION ON INTERCOSTAL PANEL. FABRICATED NEW INTERCOSTAL PANEL AFT CARGO LOCATED & DRILL NEWLY FABRICATED INTERCOSTAL PANEL AFT CARGO INSTALLED NEWLY FABRICATED INTERCOSTAL PANEL AFT CARGO INBD SIDE BETWEEN BS 1420 & BS 1440 RBL 10 IAW ALL B757-300 SRM 51-40-02 FIG 8 SRM 51-10-02 PAR 15 FIG 1 & 5 SRM 53-00-04 SRM 51-30-01 SRM 51-40-05 SRM 51-40-02 ORIG MATERIAL THICKNESS .040, MATERIAL LOSS .009 MATERIAL REMAIN .031 OUT OF LIMITS.