Hi all, I'm going to do the rear pads on my zafira gsi this weekend and although i haven't fitted a set on it yet, i'm sure it wont be too difficult. One thing i'm not too sure of is, in the haynes manual, they mention a cut out on the piston and a nib on the caliper which have to be aligned, could someone please explain. I was looking at a how to by buckle which shows changing the pads but there was no mention of nibs or cut outs. Any help would be appreciated. I've already tried posting this in the zafira section, but had no replies, astra is the same isnt it. Cheers, Doug