BTW, the cowl design looked to me like it wouldn't work very well to cool the engine, so I did a little modification.

If you look at where the arrow is pointing, you'll see a heat exhaust vent. All it took was two saw cuts and some scrap wood. Since it was into the firewall, when I glued it up, I used epoxy and some glass cloth. Since the firewall was only two layers of liteply, I wasn't worried about making it overly strong as the firewall certainly wasn't.