Ken, I just re-read your post and now I see what you were saying. Sorry about that.
I have never parked my car next to a Carrera with factory rims on it to compare the depth of the back wheel lips. I'm sure it's deeper on the real thing.
The OEM Carrera lights for the boxster (correct offsets) are friggin' expensive. Aren't they upwards of $2500 or more for a set?