Rear unit removal is easy
1) Remove the pillion seat/seat cowl
2) Remove the plastic covers from just below the front seat.
3) Remove the seat bolts and remove the front seat.
4) Undo the bolts near where the front of the front seat are, these are vertically mounted and go through the rear plastics into the frame near the tank.
5) Undo the small phillips screw and pop the plastic rivet that are both found on the panel between the front and rear seats.
6) Undo the bolts that hold the plastics on either side of the lock mechanism.
7) Undo the bolt that holds the lock release mechanism (steel cable that goes through a rigid metal part, then release the captive ball that pulls the lock release mechanism.
Undo the bolts that hold the grabrail/seat retainer in place.
9) Remove the plastic rivets that hold the plastics to the undertray.
10) Disconnect the rear light connector (3 wires in, 3 out, unlike the indicators which are 2 wires in and out)
11) Pull the plastics backwards, pulling them wide to get round various places on the frame.
Assembly is the reverse of the above.
Plastic rivets can be removed by pushing the pin into the rivet and then removed with a flat bladed screwdriver to prise them out.