Remove the Piston From the Brake Caliper
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.
WARNING:
Do not trap your fingers when the piston is pressed out.
Remove the dust cap before the piston is pressed out.
Place a block of wood in front of the piston. Carefully press out the piston using compressed air.