A up date on this picture. You can see the drag anti drag wood brace in Horizontal Stab 45 degree to the spar. I have decided to detail those with balsa to give more of a glue surface and help with directional forces that the ply skin will deal with. I also added a x-brace just back of the leading edge and leveled up with balsa to have a good glue line because down in that slot will be access to the mounting bolts and other end of bolts will be reached from access plate under HS. per print . It will be plied up to the width of the base of the Vertical Stab in that area and a water tight seal will be between the top of the HS and base of Fin.