The cowling top half was cut at the proper distance from the firewall, with hot glue retainers added to keep it in place as the cut progressed. The inner surface next to the firewall was then protected with duct tape, and a wet tape was used to make a flange. After curing, the fuselage and flange were drilled for clecoes, the cowling was removed, and sanded to clean up.
The door cutouts were hot-glued back in place after covering their inside surfaces with duct tape. Layup tape was then used to create an inner door flange.
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