As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING C-4 CHECK, INSPECTION REPORTED INTERCOSTALS BETWEEN STA 986.5 AND 967 CORRODED ON TOP SIDE. FLOOR SUPPORT SHIM AT LBL 15.5 AND RBL 15.5 FOUND TO BE OUT OF LIMITS PER SRM 53-60-51, FIG 101. FABRICATED SHIMS PER EA 53-737-199. INSTALLED SHIMS TO FLOOR SUPPORTS AND REINSTALLED FLOOR SUPPORTS PER SRM 51-40-02.