As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT WET INTERCOSTAL (LAV SUPPORT) STA 947 TO STA 967 RBL -50 CORRODED ON UPPER FLANGE. GROUNDED - YES. REMOVED CORROSION FOUND TO BE OUT OF LIMITS IAW BOEING 737-800 SRM 53-70-51-1A-1, REMOVED AND REPLACED SUPPORT IAW BOEING 737-800 SRM 51-40-02-0G-0.