Using a screwdriver, we remove first one, then the other lower part of the brake pads from the support and move the pads down.
Using a 10 mm spanner (or a special "brake" spanner), unscrew the brake pipe nipple. To avoid losing brake fluid, put a protective cap from the bleed nipple on the end of the pipe.
Using a 10 mm socket, unscrew the two bolts securing the cylinder to the brake shield...
...and remove the cylinder.
We install the cylinder in the reverse order of removal. After assembly (including installation of brake drum) we bleed the brake system from the side of the replaced cylinder.