I can help you with bulb upgrades (interior and exterior) as I did some on my PF and they made a big difference to me, in terms of looks and light quality. Also can advise with the indicators and side repeaters, I did those too
The biggest upgrade you can do your S8 though is the FE 20's as mentioned by Tintin, and as it happens, I can help you with those too
We're only half an hour from each other, we should meet soon.....
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Audi D3 S8 - 2007 - V10. B&O, Phantom Black, black and silver interior, and still completely standard with everything working as it should
SOLD 2023
Audi TT - 2015 - Ultra