Sequoia Construction photos
The panel bent around the edge is then nailed through both layers of aluminum into the wood framework. This will be covered with aluminum molding bedded in putty tape.
The various openings can be cut out with router equipped with a panel bit, or a sabre saw with the proper aluminum cutting blade.
A stick can be used to compact the putty tape around windows, doors, and vents, particularly along corrugations in the aluminum skin.