To help give a visual for this particular project here is what I am looking at.

First, the original was to use a flat aluminum sheet formed into a cowl shape.
Looking at the drawings, I just cannot see how to form, with your fingers, the nose shape where the spinner will meet. At least not out of a sheet of flat but very thin aluminum. Unless you simply made roughly, a "U" shape with the bottom left open completely from the firewall to the nose.

 This is the biggest reason I thought a 'molded' cowl would be best.

Here is what I am seeing:

Robert

I remember seeing a seafury someone built and the cowl on the nose waqs the bottom of a plastic bottle of some kind. I believe it was 1/2 a.