I have 9 and 10 Speedline for Ruf on my turbo club sport as well,
as per Ruf Tuv certificate the rear should ideally fit on 15mm spacers,
I used the 21mm to maximize rear track, the fitment is very tight with both the tire
brand I use (Toyo R888 and Michelin PS)
I tried unsuccessfully to upload a photo
Simone