I was checking the fit of the forward main spar in the first picture after I applied primer to the mating surface of the forward skins.  The skins overlap here forming several layers. This is also an area in which water can accumulate since it is the low spot of the fuselage.

In the second and third pictures various pieces are being riveted to the ribs and the ribs are partially riveted to the forward skin. They can only be partially riveted because the rear section hasn’t been mated yet and some space is needed to get it in.

The last picture shows the forward and aft sections about ready to mate.