It will help to know who mfg the kit. SIG, Goldberg, Great Planes?

If it's a SIG, and the wing is one piece, then I don't think the struts are functional, meaning they're just for looks and don't bear a significant portion of the wing load in flight. But the lower (point of the "V") end attaches just forward of the rear landing gear attach point. With the wings in place and the plane upside down, lay the struts in place and mark where the other ends touch the underside of the wing, centering them between leading and trailing edge. If they are true to scale, the forward strut is thicker (wider) than the rear main strut. There should be some sort of reinforced attach point on the underside of the wing, possibly with blind nuts for screws. There are also "jury" struts that attach between the main strut and the underside of the wing at approximately the midpoint of the main strut. They should be perpendicular to the wing suface when properly mounted. Sorry I do't have any pictures. Hope this will get you on track.