Just for the record, when I got my fast build kit, around 1990, I found that the builders had been sloppy about aligning the spars for match drilling, among other things, and some of the holes were close to the edge of the aluminum blocks in the spars.

My concern was that this would cause excessive shear loads on the edge of the block. I wrote Lancair that I wanted to install two additional reinforcing screws to help transfer the load into the composite structure and asked for their opinion. Lance wrote that they had just completed the analysis for wing tip extensions, and that was the only mod required for the added bending loads.

Later I took the fast build kit back and picked up the parts for a slow build kit. I aligned the spars carefully and added the extra screws though I have not extended the tips.