Second Oil cooler

Here is a REALLY down and dirty mock up out of cardboard.  Cardboard won't bend or hold shape like metal but I hope it will give you an idea I taped it to my cowl to hopefully give a better idea.  If of course the front would want to more streamlined .  The sides would have to be fit up to your cowl.  In the picture with  the black line on my metal extension is where it has a slight "V" (I know it is hard to see)  The compound bend would be a challenge if you don't have access to an English wheel or a good set of sand bags and metal shaping hammers.  In your case it would probably be easier ti make a foam mold and layup either carbon fiber or fiberglass.