Skins are drilled
The skins are drilled. You draw center lines on your spars and ribs to match the skin up to. It also requires a jig to hold the skeleton square. It is very different from the match drilled kits. I would verify what it is before I bought it.
Knowing what I know now, I would pay the extra dough for a new match drilled kit. However, that is coming from a guy building a 3, which has nothing drilled.