As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: DURING THE OKAY TO INSTALL RH HORIZONTAL STAB LE PNL #341B NOTICED 2EA CRACKS ON INTERNAL STRUCTURE MAIN RIB STIFFENERS 1ST AND 2ND FROM FWD TO AFT LOWER END INBD SIDE STAB STA 92.70. MAINTENANCE REMOVED AND REPLACED RIB FITTING P/N 182A5301U4 IAW DWG 182A5301 REV C AND B737-NG SRM 51-40-02-0G.