I've built several Sig Kadets MK2's for fellow club members, you are over thinking that step by far. If you built the wing correctly, it should line up perfectly, the dihedral was set with the first wing rib, if all ribs were sanded, stacked together as stated, there should be know problem with matching up. place first half on board flat,raise other half to match up with first, check allignment. I used straight edge on the leading edge. pin down first panel. use 30 min epoxy, don't go over board with the glue. Bring the halves together. check leading edge again for alignment. you can at this point block up the other half for support. tape the halves together till dry. place epoxy and fiberglass tape on joint, evenly on both halves and squeeze the glue out. this joint will never come apart. All mine have been perfect. no problems. I have a nice tight fitting joint, no gaps. If you have a little gap the epoxy will take care of that no problem. Sig craftsman kits are great to build and fly. only way that joint will separate is if you cut it in half. Hope this helps ,take your time and everything will be fine.