Page 10-13 confusion

On page 10-13, it has me attach F-01486E to the skin, then says in step 5 to slide F-01408 along the stiffeners, but that's not possible since it has no places for the 1486E, and it sits between stiffeners anyway. I can slide it along the skin J-Channel, but that means removing the stiffener I just attached (1486E). Am i missing something obvious, or are these two steps transposed?

By "stiffeners" it means the J stiffeners formed on the edges of the skin.

This is one of those things hard to describe in words....
but if you position the bulkhead so that it is too far fwd on the skin, and then curl the skin slightly to get the "stiffeners" engaged in the notches of the bulkhead, the curl in the skin will make the 1486D clear the bottom of the bulkhead.
Then start sliding the bulkhead to its proper position and everything will drop into place.

Ah, I see. I think this confused me because earlier in the page the J-Channel on the skin is an "edge stiffener", and later it's just a "stiffener". Thanks Scott.

I must have been overthinking it.