Dented the bight finisher on the tail light/door handle of my GS. Where could I get one and are they easy to change?

Theres a clip on you tube somewhere by a company called powerful UK who do all sorts of LR accessories etc.

Its fairly simple, take off the the plastic trim inside the tailgate and you then see a number of bolts, undo these and release the cable connectors for lighting and handle and its off (thats the basic overview anyway)

the clip is also linked on this site so if you perform a search it should come up for you.