When I purshased ( from Germany ) a third brake-light kit I asked Dave Greimann
on this Forum for his expert help. He supplied valuable pictures of the lower lip-spoiler cut-out and wiring detail. I was able to fit this mod myself so no special
tools or know-how is required.
However there are quite a few nuts etc to undo and a correct sequence for removal of side channells .hatch spoiler and lower lip-spoiler. Also care is required
in removing threaded screws which can become coroded and turn around without
undoing.
I would advise ordering ALL screws,nuts & bolts ,washers etc to replace at the time of fitting. Also a special screwdriver bit is required to remove the lug-nuts
from the side channells ( I made one myself using a file to cut a groove in the bit )
If the bolt-posts come unglued from the inside face of the side channells then
Araldite or similar will be needed.
Ther is quite a lot of posts on the subject of side channells and hatch spoiler removal ( but not on the third brake-light as this is US spec only ) on the UK Forum
www.968UK.com
Best of luck
Cheers Shaun ( London UK )