Here is my rough cut layup. In the photo the center will need to be braced up and the angle flattened before I add the composite. I used 2 2'x4' squares of pink board.
I layed it up by overlapping the top This will make a near perfect butt finish. It may take me a couple of weeks before I can get a chance to do it in carbon.
When I mount it I am going to make a flange like is shown in the AR-5 tapes.
It will probably be 18" front to back.