Ok, I've put together a diagram to hopefully show what you need to be looking for. The drawing is over simplified, but you should get the idea. Look for a hole in the former (cross member between the two fuselage sides) and there should be a hole (can be either square or round) that will serve as a hold down for the front of the wing. If the instructions are so weak on details then there may be a dowel hole already drilled into the wing for a dowel to be inserted.

If this still doesn't help is there any chance you can upload some pictures of the fuselage, wing components, scan of the the instructions??

Hope this helps.

Ken