While a young DC3 first officer, I recall being told that the spar was just two end-sections, held abutted together by these nuts and bolts.
I've mentioned before on Pprune about my regrets of not buying a little book of DC3 'mishaps'. Rather an understatement.
One picture was of a missing port wing...not far out from the bolts. It had somehow got back after hitting a mountain. The comment: "I bet this got their attention."
Anyone know about this book? It was on sale in a flying school near Austin some 15 years ago.