Here you are a diagram that showes how to attach these slanted parts to the model.
A. This way is quite easy.Firstly you have to bore two holes in the front edge of the flaps. You have to remember the diameter of a drill bit has to be the same with the one of the wire but thinner than the thickness of the front edge of a flap.Two piece of the wire have to be glued with the CA glue to the flap and the lower inner side of the wing half.
B. This way is similar to the A one. But there are attached two styrene cubes into the inner space of the wing. In both cubes there are drilled holes for the wire.But before these additional parts can be attached you have to bore holes in the flap edge and glue into them the pieces of the wire.It is important because these styrene cubes have to be set at positions firstly in accordance with axis of the wires in the flap.
So think over whether you can do that and if you have a such thin drill bit and wire.If not, we will find another way for attaching of the flaps.