Another thing I see in the pictures is the plywood bearer. They flush into the firewall with small triangular stock holding them. First time you go over on the nose, there goes the mount - the required support is just not there. Wood bearers are usually maple or a similar hard wood and run from the engine back through the firewall to the next former back. They also generally are glued to the fuselage sides along with the bulkheads they pass through. There is a lot of stress on this part of the airframe and they learned long ago how to build them so they don't break.

Hogflyer