[album]438[/album]
[album]439[/album]
Used cardboard and tape to make a rough version and to get the clearances right, then cut out the pieces from aluminum and took them to a shop to get welded. It's secured to the hood with the original screw holes.
I've considered adding thin strips of foam rubber around the edges to improve the seal, but I have the clearances pretty close and it does a good job as is. There is about a 3-5mm gap all the way around which allows for engine movement. I had to file down the back edge in particular after driving around because the original clearance was so close that the intercooler was rubbing against the duct when the engine moved.