WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Handsets For V70, S80 And S60
Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 2: Rubber Grommet Connector
Courtesy of VOLVO CARS OF NORTH AMERICA.
Disconnect the connector. Remove the rubber grommet.