Hello Tim. Just resurrected a "Valkyrie" that we had from the 70s. Several of the skewers are missing and I'm not sure about lengths. I assumed that the skewers for the leading edge spars would go the full length. However, after looking at your Delta kite plans, that may not be the case. The kite measures 48" along the leading edge; vertical length is 33"; width at the bottom is 70". Any recommendations would be appreciated.
Looking at an image of that original patent for this kite, it appears that the leading edge spars terminated about half-way between the nose of the kite and the attachment points (on each leading edge) for the spreader. That is, the rod which keeps the leading edges apart. This distance does not have to be precisely set, as long as both spars are identical, and the kite does not end up nose-heavy.
When dropped, the kite should float more-or-less vertically to the floor. If it takes off forwards like a paper plane, it's too nose-heavy.
It's very helpful if the leading edge spars are also matched as well as possible for weight and flexibility. The leading edge spars go all the way to the tips at the trailing edge of course.
Hope this spells it all out sufficiently :-) (Short of providing a figure in inches...)
Another thought - if you look very carefully at the leading edges of the sail, you might just spot some clues regarding the exact spot occupied by the upper tip of the original leading edge spars. A bit of wear and tear in the cloth, the stitching ... something?