Fawcettandrew
I may have used the wrong choice of words. It is a little difficult to see in the picture but the upper vertical area of the stringer is bulging out slightly for pretty much the entire length. The other stringers that I can see do not have that bulge. As far as I am aware the fiberglass under the sole should be flush against the stringer, except for the raised area under the head. In mine part of that area is directly the stringer so there is a large gap.
Hope that helps.
Manny