I didn't want to cut out or drill in to anything, doors or A pillars so for now I made a simple adapter that fits in place of a factory mounted tweeters.
Tweeters that I have are around 42 mm in diameter (from an Excursion SHX-6C set) and they simply snap into place.
Although it was originally made for a Peugeot 207 it's confirmed that this adapter also fits 406. I think that it'll work for pretty much all of Pugeots as well as Citroens (from what I can see online).
There is a STEP file attached so feel free to make any changes.
Filament:
PETG won't work, it'll just melt. Ask me how I know :)
I would recommend ASA, ABS or Nylon like I have used. PC would be great too. Basically any high temp filament.
The author marked this model as their own original creation. Imported from Thingiverse.