The inlet diffuser duct is made up in two parts. make the bottom shape and then fibreglass over the shape. Then build up shape on the inside and fibre glass over that. The inlet hole i used a CAD program to design the eliptical profile and then my CNC milling machine to mill the shape out of some wood. I then layed up the inlet shape in that as a mold. At least the two inlets are exactley the saem shape. Nothing else on the cowl is truly symetrical I can assure you. Not how it was origianlly or anything I have done. Which is OK as the engine isn't symetrical either.
