focus rear brake piston

later fords have left hand rewind on one side and rh on the other. rewind tool is left handed, right handed or ambidextrous (the best sort). if you try to wind it one way and it feels even vaguely tight then do not force it (you break the mechanism inside), try in the other direction.

the best sort to buy is the alba type such as ebay item 360152611208, there are other similar ones too.

I've always just used a pair of long nosed pliers to wind the piston back in.

Thanks Mrc

I bought the laser one from halfords. Hopefully it will work.

How will I know if its the wrong way I'm going as rears are normally pretty stiff ?

you will find that it will turn a little and then go solid (if you are going the wrong way) Rear pistons should not be 'very' stiff to turn, ideally you should be able to turn them with a pair of pliers although pushing them and turning may be difficult to manage.