Hi George,
I think I can see your description, however, although the bars may be different depths, they are all the same at the corners. All have a 45degree mitred corner producing a mortice tenon end - no changing of angles are required. A quick replace tool at the end of a spindle motor is what is required. As previously mentioned it is only the machining at the end of the bar that is required. The shape of the timber has already been done.