What was found
AFT BAG PIT DOOR SURROUND FLOOR STRUCTURE JUST INSIDE DOOR ON AFT END CORRODED AT SCREWHOLE. GROUNDED - YES. REMOVED CORROSION, ORIG THICKNESS=0.100"; REMOVED:0.15"; REMAINING:0.85" FOUND TO BE OUT OF LIMITS IAW B737-900ER SRM 53-60-15-1A-1. REMOVED DAMAGED THRESHOLD STRAP, LOCATED & DRILLED NEW STRAP P/N: 146A8128-14 PO:0 & INSTALLED IAW B737-900ER SRM 51-40-02, SRM 51-40-05, BAC DWG 146A8120 REV A & BAC DWG 146A8120 REV-.