Please be aware that this is NOT the Nissan suggested way of doing the rear brakes.
You will need
Socket set with 17mm socket, 14mm Socket, and extension bars.
21mm Socket or Wheel Jack
Brake Piston winding tool
WD40
Jack and Axle Stand(s)
Firstly jack the car and secure with an axle stand, if needed use a brick on the front wheel to stop the car rolling.
Remove the rear Wheel.
Release the handbrake.
A 17mm socket, is used to remove the caliper.
Then pull it off the disk, old disks with a slight ridge may make this harder, just use some brute force.
Undo one of the 14mm bolts on the caliper, swing it open.
Remove the other 14mm bolt and you should be left with this.
Dont worry if this happens, just stick it back on.
Take your WD40 and spay where the pistone meets the rubber, otherwise when we try and wind the piston back in it will bind on the rubber and make it even more of a b1tch than it already is.
Remove the cap from the brake fluid bottle in the engine bay.
Now wind with the tool availale for about £10-£15 from many places, or improvise.
You need to wind it back in until its almost flsh with the caliper, maybe 4mm out whatever the rubber squashes too. It is VERY IUMPORTANT that it finished with one of the notches perfectly down, as you will see in the next steps.
Then reassemble the new pads in the bit you removed.
Get back to the swing position
Rotate back into place, now you will see if the nipple on the pads aligns with the piston, if not - adjust.
Now its in you will see if theres enough gap for getting the disk in, if not wind the piston back more and try again.
Now finish the job by putting it all back together.
Wheel back on and to the other side. If youve taken under 20 mins your lucky, over an hour and your unlucky (per side).
Hope this was useful.