I'd start with a piece of insulation styrofoam about 2" thick cut to the size you want, layout the area for the pavement and the ditch and start cutting. Paint with flat latex paint, gravel and grass are available in the train section of most hobby stores. Use a lot of reference photos for details. Good luck.
Another little detail I didn't notice, this particular intake has fuel injection nozzles plumbed into it, haven't ever seen that before. Usually the fuel is injected at the air intake to help cool the supercharger, maybe this one had both?
Looks like it fits over a short dragster chassis. http://www.speedhunters.com/wp-content/uploads/2015/10/California-Hot-Rod-Reunion-2015-88-copy.jpg http://www.speedhunters.com/wp-content/uploads/2015/10/California-Hot-Rod-Reunion-2015-91-copy-1200x800.jpg