IJK, I have thought of them and used them before. The idea is that you use the wheelbase of the tractor to get it smoothed out, also that it can get into tight places when you remove the loader and hoe. Back in the old days all the makes of garden tractors had them available. I think partly due to the fact that they didn't have real 3 pt hitches but it worked well for taking down the high spots and dragging it to the lows. Well I guess I just have to design one and give it a try. I'm thinking that about a 5 ft blade should be good, start with a manual angle, not sure of the best way to make it a grade angle yet so need to think that out. I've been at the barn build now for over two years due to the contractor skipping out on me...well it's ready for the inspector and hope he doesn't find too much. So with luck I will have a little time to come up with a design and fab it up.....