Great looking car! It looks like you need the 
 roll bar inserts
roll bar inserts as well. I had to get them when I got my Boxster. They are pricey new so I bought mine from eBay. You might want to think about Jay Senoff's windscreen. It takes care of buying all three of the inserts in one shot. He is a forum sponsor and has a 
link at the top of the page. I have his 
rollbar inserts and am very happy with the quality of the product.