Can't upload any pics right now, I'm on my iPhone. And yes this mod is strictly cosmetic. As Fseth mentioned, 4.6/4.8 only came with these arches and I believe a euro special edition 3.0 came with them. You can check out the whole kit for that euro 3.0 @ ecs tuning. Pretty easy install also.

what is the width and the offset (ET value) of the wheels you put on?

I just ordered 8.5" wide ET30 offset Beyern Rapps and am wondering waht size spacers I'll need.
I currently have a set of 15mm spacers for the fronts and am wondering if 20/25mm will be perfect for my rear set up as well.

Hmm I'm not sure. They are the standard BMW style 87s (non staggered) maybe someone else can chime in with the correct number? It's a very common wheel

Naz24, are they the 20" OE wheels, or 18" or 19" replicas by chance?

20 inch replicas. They are the same dimensions as the oem though. My set up is non staggered (so the rears are the smaller width, same as the front ( as what would be found on the front of a 4.6is)