As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT CARGO COMPARTMENT; STA 727A + 14 TO 727B LBL3 WL160; INTERCOSTAL HAS CORROSION ON RH SIDE. / BLENDED CORROSION ON INTERCOSTAL IN AFT CARGO COMPARTMENT STA 727A TO 727B LBL 3 WL 160. OUT OF LIMITS REPLACED INTERCOSTAL IAW BOEING DWG# 146A7500 AND 737 SRM 51-40-02-0G-0. FOUND ORIG T .040' LOSS .021' REMIANING .019' OUT OF LIMITS IAW SRM 53-00-53-1A-2