1. Replace the original exhaust pipelines Dwg. No. E6 18-11 01, E6 18-12 01, E6 18-13 01, E6 18-14 01 by the modified exhaust pipelines Dwg. No. E6 18-23 01, E6 18-24 01, E6 18-25 01, E6 18-26 01. 2. Record the bulletin implementation in the Logbook.