Pulling cutting wire into car:

WARNING: This page is about a different car, the 2002 BMW M Roadster, 2002 BMW M Coupe, 2001 BMW M Roadster, and 2001 BMW M Coupe. However, it is still accessible from the selected car via links, so may be relevant.

Push wire starter (2) from inside at a suitable point through adhesive bead
Feed wire end (1) into hole of wire starter (2) and bend back
Pull in both wires in succession crossways

NOTE: Crossing the wires cuts through the adhesive bead completely.

Fig 1: Pulling Cutting Wire Into Car

Courtesy of BMW OF NORTH AMERICA, INC.