Connecting sleeve for the installation of 55.0707.00 on the 50.0932.40 / 50.0933.40 / 50.1014.40 / 50.1023.40 / 50.0990.58 / 50.0990.78 / 50.0991.58 / 50.0991.78 rear muffler and Connecting sleeve for the installation of 55.0649.00 on the 55.0707.00 centre muffler