Process
 

here we go, usual cautions when jacking up a car, use axle stands etc.
Take the wheel off, and turn the steering so that the caliper is towards you.

There is a flat metal spring that locates the pad carrier, insert 2 flat screwdrivers at the position of the red inner arrows and prise it out. There is a fair bit of tension, so be careful as it comes out in a big hurry. (Caliper assembly.jpg)

The spring when it's off looks like this ( Spring retainer.jpg)
On the inboard side of the caliper, locate the rubber caps, top and bottom, that conceal the hex bolt heads that retain the pad carrier. circled and arrowed. (rear of caliper .jpg)
Remove the rubber caps, put to one side for replacement.
Undo the 2 hex 8mm bolts. (remove hex bolts.jpg)
Lift out the pad carrier assembly (pad carrier off.jpg)
Compress the piston back with a large G-Clamp

Change the pads out, reverse the process.

Refitting the spring is a pain.
Look again at pic 1.
Hook the spring in a the bottom first, lower red arrow, hook the centre tag back in the caliper body, and prise the top of the spring back, upper red arrow.