Well, after bending and cleco'ing four or five times in my attempts to close all the gaps, it's finally riveted! Both Katie and Jeremy ended up stopping by to help me squeeze the leading edge while the other inserted cleco's. Phew...glad that's done. Must still roll the small section at the end, but I don't anticipate issues there.
Had to drill out one of the pop-rivets. Turned out to be a piece of cake. Not sure what these guys are talking about when warning others about this.