i presume you have a Zaf B as its in this section...
to remove the Zaf A rear bumper ..
open the rear tailgate
underneath the rear bumper ,undo all the screws that hold the bumper to the rear panel.
at the rear of each wheel arch remove the 2 securing screws ..
then support the bumper and undo the 2 top mounting screws and remove..
pretty sure that the Zaf B will be the same...