What was found
FORWARD CABIN SEAT TRACK -Y450, FLANGE IS CORRODED AT FRAME 18. REMOVED CORROSION & FOUND OUT OF LIMITS IAW SRM 53-10-16. D= 0.046" MAX PERMITTED 0.012", L=3.0" W=1.50". REMOVED SEAT TRACK IAW SRM 51-40-21, LOCATED & DRILLED IAW SRM 51-40-44, PN A5361251820002. INSTALLED NEW SEAT TRACK IAW AMM 51-40-21.