I used a leftover piece of stripped bulkhead to construct the skeg.  I decided I didn't like the wood spacers along the top edge of the skeg.  Instead, I installed 3/4" long pieces of PVC pipe in three locations on the skeg and epoxied them in place.  They are positioned so that they won't interfere with the bungee.  The hole for the retraction line was filled-in with thickened epoxy and then redrilled.

The small block in the lower right corner of the trunk is the combination stop block and bungee anchor.  When assembled, the ends of the bungee loop will pass through the grooves and will be knotted on the interior of the trunk.