Thanks Rhaven Blaack, I like that! It appears the neck and the torso will need this.
(All of these assemblies were done before Rhaven's excellent suggestion above.)
This view shows the extra strips of paper inside the model to help hold the legs to the waist. (In this shot only one side of each strip has been glued.)
The arms - pieces 71-74.

The two parts that make up an arm fit without gluing surfaces.

You can see the extra long "non-gluing" tab inside the arm from the forearm that helps hold the piece in place

I guess the idea is most of the pieces are just supposed to have a snug fit - but that won't do as it leaves gaps between the pieces and I'm a little rough with my toys.

So here I snipped the long tab inside the arm and bent down part of it to make it a gluing tab. Also when the pieces were merged a little glue was put on all touching surfaces.
Arms are ready. Torso with one pec attached. The pecs barely covered the white guide area underneath so using the black marker really helps.

Here is the neck -piece 75.
A trial fit shows that the head and the neck won't go together without a fight! :blackeye:
Next up, fight the neck, add gluing tabs per the excellent suggestion and then attach the head/neck to the torso and the torso to the body...