As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN HEAVY MX PERFORMING INSP IT WAS NOTED THAT AT STA 950A, STR 29L THE INTERCOSTAL IS CORRODED. REMOVED DAMAGED INTERCOSTAL AND FABRICATED NEW FROM 7075 T6 .040" DIM 8.875" X 19.625". INSTALLED REPAIR, NO OTHER DEFECTS NOTED. ACFT WAS RETURNED TO SERVICE.