The Carbon Fiber looks good too, I think it depends on the interior color, gauges, etc.
I used an X-Acto # 11 blade. Angle it about 45 degrees to the opening, so you are just skimming the edge of it, and gently run it around the circumference. Making 4 separate pieces may have been more work than was necessary, it might actually be easier to attach it as a single piece and trim the edges.
This is what I used, they have all kinds of patterns and colors available.
http://rover.ebay.com/rover/1/711-5...0001&campid=5335822911&icep_item=331440474382
-Dave