What was found
FWD, LH LOWER WTB PANEL LANDING INSIDE ACCESS PNL 193AL HAS SURFACE CORROSION. STICKER #83-003. ATA 53-30. REMOVED 1EA CORRODED WEB FROM INTERCOSTAL ASSY. INSTALLED (15EA) NEW NUTPLATES ON WEB P/N 149N7125-41SAAU, IAW DWG 149N7125/SAMPLE AND B757-200PF SRM 51-40-02-0G-0. OK TO INSTALL 1EA WEB AND 1EA INTERCOSTAL ASSY. INSTALLED 1EA WEB P/N: 149N7125-41SAAU AND 1EA INTERCOSTAL ASSY AT LH LOWER WTB PANEL LANDING BTW STA 860 TO STA 900 LBL 31 IAW B757-200PF SRM 51-40-02-0G-0 PARAG.4 AND 7.