HELP......I am thinking of.....

[Amigo GT500]

widening the rear wheels of my Shelby '12. It would be the wheels what comes with the SVT package. (Tires: P285/35ZR20)

 

So my questions are:

 

 

1- how wide can I go (rear wheels - 20") without touching the fender?

2- What would be the right tire size? I would like to keep having the same brand (Good Year)

 

This company would do the widen http://weldcraftwheels.com/index.html

 

Thanks for your advise.