What was found
LEVEL 2 CORROSION, UPPER FUSELAGE, PASSENGER CABIN, FR 20 AT Y 765 SEAT TRACK CORRODED. REPLACED THE SEAT TRACK, FR 12 & FR 24 IAW SRM 53-11-15-01A, FIGURE 001, ITEM 015-A, REV 158.00 AND INSTALLED IAW DWG D53112812, ISSUE E, SHEET 01, DWG D53110900, ISSUE L, SHEET 08, & DWG D53110984, ISSUE B, SHEET 01. (LP: 1791535, AIRCRAFT WAS GROUNDED)