707 wing
411A - you're talking about the wing "glove" installed on the 707-100's? If so, that was a fix to some handling characteristics - not sure exactly what, but I vividly remember removing the glove panels and seeing the "old" wing skin underneath.
Was an interesting time, indeed. The 707 had a lot of interesting structure, including spot-welded skin-to-stringer joints, the good old scrim cloth in the lap seams, and other fun stuff I hope I never see (or have to repair) again.