Scirocco Central

I'm looking for some help determining the right fitment for my Scirocco and BBS RM rims

I'm going to rebuild the BBS RMs and add a bigger lip but not sure which size is the best fitment.

Hopefully someone can help.

I was thinking
Rears 15x8.5 or 15x9?
Front 15x8?

Here is what I'm trying to achieved without cutting up my car.

Keep the front a rears the same size. Just because it would b easy to rotate the tires for even wear.
8" Rims should be enough. Well it depens on what is enough does it not?
What size tires are you planning for the 15" rims? 235/50/15?

As you are rebuilding the wheels car you adjust the offset to move the wheels out a bit? Some people are adding adding 10-15mm spacers to original wheels to get a more flush look.