Trolley jack and a pair of axel stands does the job nicely. If you haven't got them yet, you might as well buy some - owning one of these cars you are going to need them!
Order a few spare under-tray fixings before you start too, they rust in place.
I found a small phone mount suction cup was ideal to pull the light unit off its pop retainers.
As the others have said, jack up, axle stands, remove undertray and with a long reach 10mm undo the rear retaining bolt that comes out downwards then remove the light unit forwards.
Thanks - I might purchase those. It's pretty cold to do anything much at the moment!
The reason to replace is that one of the sidelight bulbs failed. It didn't last long either. The yellowish (but long lasting) bulbs were replaced with halogen Philips WhiteVision W5W (501) which look much better with the factory HIDs. Or maybe they were the Bluevision - I can't remember. I think the Whitevision are 3400K and the Whitevision are 4300K (both halogens) or something like that. They could even have been OSRAM Cool Blue Intense W5W. I've bought a bunch over time for different cars.
I do now have a decision to make.
I have a replacement pack of the older Philips Bluevision halogens.
I also have a set of LEDs - Philips Xtreme Vision 360 LED W5W T10 4000K. There is also a set of Philips CANbus Control Unit - basically, resistors with heatsinks and flying leads.
So - should I change to the LEDs? If so, is there somewhere safe to patch in the resistors, and cable tie them to (they get are supposed to get quite hot). I checked one at it is 92 ohms. So if voltage is say 14.7V, then 14.7/92 = 160mA --> 2.4W
I can see why "CANbus" cancelling LEDs with the resistor onboard would fail fast!