I use the Xtreme racing carbon fiber conversion kit:
http://www.xtremercracing.com/Store_...ShowLarge=True
I think i might be the only one on here that is using it. I have it in my racer and has been carried over from my LST1 to my new LST2 which sees a lot of track time. Pieces fit really nice and i like the fact that if need be, you can order replacement parts individually. Being that i dont have a piece of plate aluminum on my whole LST surely cut back some weight, and like i said they have proven to be very durable.