I'm borrowing from Tim Olson's design for mine, with some modification:
Around half way down the page, are pictures of the design for building his slow-built wings. Dimensions of the primary 2x4s are in a nearby pic. Further down the page is the modified design used when his wings reached the stage our QB wings are in. I think that I slightly shortened the long 2x4 rails so as to be sure that I could work on the landing/taxi lights without any of the rack being in the way.
My wing rack is not quite finished and is untested. It's currently at our company hangar (45 miles away) where the kit is temporarily stored awaiting the transformation of my basement into a shop. Thus no work done on it this weekend and I'm flying all day tomorrow. Hope to finish it up Tuesday and test fit the wings to the rack. One final detail that I haven't fully worked out yet is just how I plan to secure the spar end to the rack. Planning on using the plastic tubes that protected the bolt holes in the QB fuselage spar carry-through in it's crate...if I can find them. Smaller bolts through those plastic tubes would be adequate, I think.