Technical 15" rims on x1/9 TUV paper

[ovidiuaproporo]

I plan to mount 15" rims on my x1/9, but I need an official papers from a fiat dealer / service / factory that say it is possible to mount thoose wheel on this car. Anyone in here have this paper to omologate this new wheel dimension? know where I could get this paper ? Thank you all for future answers.