The last time I bolted a trainer wing down. I removed the windshield piece of the plane and cut open the bottom of the wing fwd of the spar to the leading edge and fitted balsa blocks in ( hand Sanded to fit the contour of the wing. Then I drilled through the bulkhead fwd of the leading edge of the wing through the windshield piece that I removed. I installed dowels to hold the leading edge down. The trailing edge I fitted a hardwood ply piece and installed blocks inside of the fuse. Drilled down through the wing trailing edge into the blocks. Threaded them for 1/4 - 20 plastic bolts and then thin CA glued the threads. The blocks in the wing I used 5 min epoxy and on the dowels as well. I also fitted forward of the bulkhead a plywood doubler for extra strength.

Total process with breaks was about two hours.