Engine Plenum.

I decided to build an engine plenum chamber for cooling, rather than using baffle material pressing on the upper canopy. This configuration also reduces pressurization of the cowling.

Here's a photo of the cardboard mock-up, defining the shape of the plenum cover. You can see the bends required to follow the engine/cowling shape. I made the top in two pieces, left & right, overlapped at the center on a piece of .063 angle with #8 nutplates on the angle. I made the two pieces from .032 aluminum, bending the edges to fit inside the baffle sides, with #8 nutplates about every 2".