t observer seat was reupholstered (outer cover only) with Spinneybeck Leather: PN 6043ADI I 2152FT- Andes Color 6043 D/L 11215217. In accordance with Aviation Consulting & Engineering Solutions Inc. Substantiation Report No. A0619I7-03SR Rev IR dated 8/25/2017, and ACES drawing GVSP-090024 Rev IR dated 8/25/2017, and approved via FAA/DER 8110-3 dated 828/2017