Fit the wing spar box inside the fuse (multiple times)... Installed the wings and tied to spar box for alignment
Drilled holes and bolted spar box to fuselage with AN5 bolts
Fit and check the alignment of both wings while in place. This required multiple fittings of the wings to get things right.
With the wings in place, centered and aligned, the top tabs were back drilled and AN3 bolts fastened to hold the Spar Box together. The whole assembly is shimmed with washers and bolted tight.