Vito 639 tailgate trim panel & wiper problem

I have a fault with my rear wiper, which according to other posts could well be water in the motor (http://www.benzworld.org/forums/v-class/1628207-rear-wiper-w639-3.html).

Basically, the wiper wont stop going and the only way to stop it is to remove the fuse (F7).

But, I need to get to the motor which is behind the tailgate trim panel.
I can remove the trim clips to loosen the board panel, but how do I get it off past the door handle/lock?? Does the handle come off or am I missing a trick??

Any help appreciated!