Cosmo, You are right. It is an overlay. You remove the glass and put the carbon fiber down. As far as structural intregity. I have been trained in structures and would never sacrifice safety. My shop builds show car, everyday drivers, and race cars. I just got a 02 WRX for myself and started to buid it. I will send pics soon. I have a roll cage in it. And I have started the widebody. My wheels are 19"x9.5" You can ask any body or paint ?s you have. I will try to anwser them. Thank for your input.