Back wings off. Tailgate off which means the torsion springs too.
Support the back of tyhe floor and remove the body to chassis mounts.
Unpick the welds to the rear door fram uprights, might be worth checking they are still fastened to the floor
Separate from the floor and remove. You should find the floor does not rest on the whole of the surface, rather it touches where the edge of the panel is bent down for strength.
Yes it's a bot of a job, check and double check you have got everything square.
The one I'm doing right now, someone has already been there and it's not entirely as it should be :roll: