Removing parking sensors with bumper in place

[wokfm]

Does anyone know if this is possible (on the rear of an A4 Avant).

I can just about get my hand behind the bumper and on to the sensor on the side/left rear, and Haynes quote "simply (yeah right!) press the clips outwards", but I cannot work out which bits are the clips, as I can only feel my way. Has anyone got a clear picture of the inside rear of the bumber - IE when removed; or even a picture of the sensor itself, so I can see what these clips look like and work out how to release them.
I'm sure it must be possible to get this out without removing the bumper - which appears to involve as much as removing the rear seat, in order to remove rear load side pannels, and then floor etc. Something i'd rather avoid if possible.

Rich

[wokfm]

Anyone? I'm really struggling with this