Feeling the fitting effort yesterday yielded a decent fit, we held the dorsal fin in place and drilled in the first few rivet (cleco) holes. After a bit of blue smoke words, and a little more moving pieces around as newly placed cleco revealed opportunities to make further improvements, I was finally able to call an end to fitting the dorsal fin. But, the final approach required two fitting flanges midpoint on the fin at the change in angle between the fuselage proper and the turtle deck.