Unidentified 1/2A Combat Plane

@Ken Cook wrote:Most kits if that is a actual kit used very poor quality plywood. I only use 1/8" 5 ply which I purchase from Sig. Using blind nuts behind the firewall or nut plates is the best way to fasten the engine. Using good quality ply would also be helpful in assisting wood screws to hold. Whenever a firewall is constructed as your model and many others, a good practice is to wrap the perimeter of the firewall to nacelle with lightweight glass cloth and epoxy. I cut strips of glass cloth 3/4" wide and wrap it around overlapping the strip. If you use blind nuts, the glass will go over the holes for them. I fill the holes with clay and glass right over them. When dry, I poke a hole and the clay prevents epoxy from going into the threads.  Slow cure epoxy works exceptionally well for strengthening, I use 30 min for these kind of models. I just hit it with a heat gun just to thin the epoxy to saturate the glass.