Open boot, in the edge of the boot by the side of the rear light are two small holes, these are for accessing the units spring retaining clips, press into the hole with a small screwdriver to realease the clips and the light unit will come out easy.
Handle with care, DO NOT DROP, remove over a soft surface, these are very expensive to replace.
One of the most subtle yet impressive improvements, whilst we all agree the Z1 is future-proof and does not look its age, the clear rear design further enhances that view. The brains behind this is Michael Kossyk of Roadster Fashion, the units were sent to a designer who laser cut the amber lens off the units, created a mould and recreated the deign but with clear material, then refitted to the unit, an exact copy of the original. These particular units were a limited edition run of 20 units made in Germany, and are no longer available.
As with the rear, the front indicator lens is de-coloured, what worked for me is spraying contact cleaner onto the yellow paint, it dissolved the paint, but DO NOT let it dry, pour it out straight away, respray more, agitate with a paintbrush and pour out the contents.