I'll often block the two wing panels at the correct dihedral angle, with the spars offset, overlaped. Bottom spar cut to correct length, top spar too long. Bottom sheeting in place, top sheeting and root ribs not in yet. The back of one wing's main spar resting against front of the other. With the bottom sheeting as the guide for having the wings spaced, I razor saw straight down through the top spars and bottom spars. The wings fit together perfectly every time.
(Its easier to show than describe...)

You just about can't install the root rib correctly until the spars are cut unless you go through a LOT of work with the carpenter's square and dihedral guage. This method... the center ribs gets installed flush with the perfectly cut spars.

You can laminate all root ribs together then glue that into one wing... along with the dihedral brace(s) let it set up, then join up the wings. the laminated root rbs guide the spar, LE and TE locations, the dihedral brace guides the angle between wings. It gets VERY easy from there. [img]i/expressions/face-icon-small-wink.gif[/img]

30 min or 2 hour epoxy for joining the Kadet Sr wings. (2 hour preferred) Quicker setting epoxy won't gve you time to do it right. LOTS of pins and masking tape to hold things in place! (stick pins in a bar of soap before sticking in the wing... they slide out of the epoxy easilly after the stuff is set up. Twist then pull.)