If you are patient and keep your eyes open, affordable parts sleds will eventually come along. As far as the holes, I think that you are referring to the triangles in the "x" frame. They don't need to be there. Kawasaki took the metal out to keep the sled as light as possible. It is really there just to keep the bulkhead true. I think that Kawasaki did a nice job keeping the sled light, but in some cases they are using only the bare minimum to keep things together. If you wanted to replace it with some sheet steel it would do the same thing but just be a little heavier.