I like the concept and general look/feel of the image. I hope you took a whole bunch off them (or intend to). I'm sure it will be tricky to get the balance between the ambient light and the flash. I think the flash is a little "hot" here. I really, really like the feel. The metal, the shapes, the rust, the green light - all good. Maybe also think about going closer - not necessarily including the whole car. Close up of a strong car element with glow in interior as background. Love to see some more along this theme. Maybe have lights underneath car, have it coming out of the engine bay with bonnet up (I think American's call it a "hood"?). Set in a rustic scene, I think yoy have a real winner here.