This is were it gets slightly complicated. Put the inner shaft into the middle shaft, making sure that the pin side is aligned with the hole near the bottom of the middle shaft

If you want, you can also lubricate the bushings.

The finicky part is trying to get the inner shaft past the upper bushing. The inner pieces of the upper bushing are a bit flexible. They should be flat against the walls of the middle shaft, but you can always push your finger in there to press them out.