Since I am not using the standard propeller/spinner, I had an issue with the clearance between the spinner backplate and the inner diameter of the cowling opening.

I had to enlarge the inner diameter, so I made a template out of plywood in order to make a nice radius.

I used a Trim Router to create the inner radius.

After some more trimming and sanding, I added release-wax to the template.
I then trimmed the cowling and sanded the edges to an angle for more contact surface for the new epoxy.

I prepared 3 layers of fiber, and carefully arranged it on the cowling and template.

After it had cured, I removed the template and sanded down the new cowling edge.

I then prepared the upper cowling for a new edge.

With the upper cowling in place, I added 3 layers here as well.

After that had also cured, it took a little trimming and sanding to finish the upper cowl.

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