I rolled the leading edge per plan. No issues. I used a 1 inch steel pipe from one of my wood working bar clamps. I duct taped it to the skin and used a monkey wrench to turn it. I turned with one hand and held it down against the table with the other hand. It turned easily all the way it would go. I did both sides, being careful not to smash the rolled side when I did the second side. Then the two halves didn't come all the way together due to the taper. So I just massaged it with my hands and that worked great to bring the holes in alignment. I don't see puckering. I pulled some rivets and call it done.