PS -- Neither of the ribs shown includes the leading edge structure.
In one version the leading edge detaches and is in fact, a fuel tank.
In another, the leading edge contains a portion of the wing folding &
latching mechanism.

But in most cases the Leading Edge consists of a single piece, routed
from 1/8" plywood, with notches to accept longitudinal stringers. In
most cases the leading edge itself is fabricated from 1/32" or 1/16"
aviation-grade plywood. In another experiment it is urethane foam
covered with fabric or... whatever.

I've posted some pictures of the ribs on my blog.

-Bob