I honestly think this every single time I pass one of these signs on the highway. Don't think I successfully imparted the idea of a vehicle just sailing off the edge of a cliff - it looks more like a simple crash, rather than a freeze-frame of the action.
After a few attempts at reworking the truck off on a separate sheet of Bristol, it seemed to be making it worse, or at the very least not "fitting in" with the rest of the composition. Sometimes I think it's a crucial aspect of a successful composition to get everything down right in one shot with one sitting per scene. And I think this discongruity can at times be seen, as it can affect the aesthetic flavor and feel of an image by giving it a slightly offset look. After so many years of digitally rearranging elements for graphic design work, it's a sublime satisfaction to successfully compose all the elements into a matching, unified style.