sweller says...[QUOTE] Yeah, the one in yellow's gagging for it. They're pretty excellent fun cars - you can get loads in them.[/QUOTE] I once cut a 30" by 36" hole in the roof of Ren 4 to fit a Britax fold back fabric sunroof. When I went to get the sunroof framework the car sagged in the middle by 3 inches. We had to use Accro props to pull it out before fitting the frame to give it back some strength.