Thanks peeps, will get on to this on the weekend.
Once I take the fluid out do I leave the resivour cap off until I have pushed the piston back in or just take out what I need to, replace the cap, then go work on the calipers, push them in, start the car and then refil if required? Or am I missing a few steps? Is it ok to give one of you guys a call RE this just to run through it?