I've just had to replace the spoiler mounted brake light, so I thought i'd do a 'How To' for anyone needing to replace theirs. There doesn't seem to be any aftermarket versions that I could find, so you'll need to find a 2nd hand one or maybe try the main dealers.
Step 1: Removing the spoiler
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There are 3 nuts and a couple of plastic clips that hold the spoiler to the car. Open the boot and remove the 3x 8mm nuts. There is one at either end under the black rubber covers, and another located in the middle underneath the plastic trim that surrounds the window. The trim is just clipped on but it's very tight and requires some force to remove. Once the 3 nuts are off then the spoiler is only held on by a couple of plastic clips and the wiring connector. Gently pull the wiring out of the hole with the rubber bung, and then unplug the connector by pressing the catch as you pull it apart. With that removed simply tap or pull the spolier upwards and it should come free of the plastic clips easily enough.
Step 2: Removing the light from the spoiler
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With the spolier removed there are 2 bits of plastic tape on the underneath of it, pulling these back reveals 2 phillips screws holding the light to the spoiler. One of mine came out easily, but the second one was just spinning in the rusty thread and i ended up having to drill it out. With the screws removed, use a screwdriver to reach in through the same holes and gently tap the brake light out, it's not bonded in but it does require a couple of taps to free it from the seal. Refitting is just the reverse of removal.
Step 1: Removing the spoiler
--------------------------------
There are 3 nuts and a couple of plastic clips that hold the spoiler to the car. Open the boot and remove the 3x 8mm nuts. There is one at either end under the black rubber covers, and another located in the middle underneath the plastic trim that surrounds the window. The trim is just clipped on but it's very tight and requires some force to remove. Once the 3 nuts are off then the spoiler is only held on by a couple of plastic clips and the wiring connector. Gently pull the wiring out of the hole with the rubber bung, and then unplug the connector by pressing the catch as you pull it apart. With that removed simply tap or pull the spolier upwards and it should come free of the plastic clips easily enough.
Step 2: Removing the light from the spoiler
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With the spolier removed there are 2 bits of plastic tape on the underneath of it, pulling these back reveals 2 phillips screws holding the light to the spoiler. One of mine came out easily, but the second one was just spinning in the rusty thread and i ended up having to drill it out. With the screws removed, use a screwdriver to reach in through the same holes and gently tap the brake light out, it's not bonded in but it does require a couple of taps to free it from the seal. Refitting is just the reverse of removal.