They get melted down for pots and pans so the rivet holes don't matter. Plenty of ally cookware all over Africa. Rumbek has what's left of a 748 just up the road from the airstrip. The entire aircraft has been cut up except for the heavy centre bulkhead around which the fuselage is built, and to which the main spars are attached. It's all that's left and that was a couple of years ago. Probably also gone now.