Here are a few pics of the beast coming together:
It has my approval. I could use it with my 60hp 2wd for general duty. If it is suitable for land learing too, i have to see how the blade and the back blade are tied together. A plate welded between them, backing both cutting edges so they carryan impact load together would approve. Also, how is the cutting edge attached ? will the bolts rip out of the plate when hooking it behind a 10" tree stump (which i take down with my 60hp tractor) or will it have sufficient distribution of the forces on the cutting edge into the frame ? This is a problem with the farm duty 3pt dirt scoops which are most popular here in Holland, comparable to the popularity of the box blade in the USA. We bought a heavy duty 3pt bucket and used it for wheel loader duties, digging holes so deep that you couldnt see the tractor anymore, land clearing and demolition.
the style of box you have here, is here in Holland usually a trailed land leveler because a long drawbar makes it easier to hold grade. When its a 3pt implement it will be used for a lot rougher work... but the double cutting edges tied together, may give it enough strength to do that..
For torsional stability we always weld two pushbars from the top of the top link tower, one to the rear left corner and one to the rear right corner. You need it when uprooting trees, pushing back and lifting the blade at the same time will put quite a force on it, as it will give the tractor more traction too...
Same is for a blade that leans more back, the dirt will climb up to it, giving more downforce which is required to keep it cutting when the load starts to heap up in front of it.
To us it behind the 8970 i'd want it to be wider than the tires, easier to hold grade and easier to dig holes or go around fenceposts.