I have a stone (retaining) wall on one side of my house. There is only about two feet showing on my side of the yard, in the neighbors yard the wall goes from 2' to approx 5'. Currently on top of the wall is an old wire fence with the metal post cemented into the wall. I want to cut out the old wire and put up a cross thoroughbred fence. My thought is to use the existing metal post (cut them down to about 2 or 3 feet) as anchors for new 4x4 posts. I thought I would drill center hole in the new 4x4 post and slide the post over the existing metal post. My problem (maybe not the only one) is how to stabilize the bottom of the new 4x4 post onto the existing wall?