Single Status Update
I don't wanted to write this in the thread, but I am afraid that there is a wrong picture in your post of last Sunday (#57).
The first image refers to the DC-7B and there is quite visible the central plug for the wing extension. As far as I know it is only for the DC-7C. This could be misleading.
Congratulations on your project from a modeler that knows how challenging is to convert a 6B into a 7C.