What was found
WHILE WORKING NR 500, FOUND AFT BULKHEAD FOR WING CTR SECTION TO BE CORRODED AT RBL 7.5 AND 14.5, WL 150 AND AT BL 0, WL 165, BS 870. *S/D* REMOVED AND REPLACED AFT BULKHEAD FOR WING CTR SECTION BS 870, RBL 70 - LBL 70 PER FEDEX EA 7-5710-43764.