That is a left hand cutting tool. It was in there to cut the underside of the rook tower. In the picture, the tool holder is loosened up so the 1-2-3 block could rest against the side of the compound without interference. Thats as far as I have been able to get. The bolts holding the block are so tight I haven't been able to remove them. I was talking about that part when I mentioned taking the apron apart as I thought the cross slide was part of it.