Three final sessions finally got the Engine Pylon skins fully installed. Josh helped me out here and was game to bang those steel rivets in by hand (while I did maintenance finally on my air rivet gun). But he hasn't been back to the hangar since... too much of a good thing I guess. Once I had both side skins cleco'd in place I tried to do a nice job placing the screws for the inspection hatch and coverup my earlier mistake of riveting the whole co-pilot side skin to the top edge angle piece. Somehow I think screws are not the right fasteners to use here and that some sort of bolt & nut arrangement would be better lasting (Derrick on this site did a very professional looking job of this).