I replaced my Silver BoxsterS badge with a chrome one from the 2004 550 edition BoxsterS.
That and the clear tail lights gave it a much cleaner/high end look.
Well worth the $180.
A guy down the block has a silver 911 Cab and from the back they look kinda similar.
I also added the plastic chrome-like grill strips from Ebay for $30. Its really door edge protector strips like the kind you get a Pepboys, cut to fit the grills. A little bit of a mark up but a nice improvement. Stock Looks kind of unfinished to me
and I got one of these for $5 on ebay too (best bang for the buck!)
Try painting the center caps yourself with model paint and then cover with clear lacquer.