As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - MAJOR REPAIR - DURING C-18 CHECK CORROSION WAS FOUND ON UPPER AND LOWER SURFACE OF FLOORBEAM UPPER CHORD AT BS 328, BETWEEN LBL 29 AND RBL 32, WL 208. MAINTENANCE CUT OUT DAMAGE IN FLOORBEAM UPPER CHORD AT BS 328, FROM LBL 35 TO RBL 67; FABRICATED A NEW REPLACEMENT SECTION OF UPPER CHORD AND 2 EACH REPAIR ANGLES; INSTALLED REPAIR PARTS IAW B737-300 SRM 53-10-51 FIG 205.