Adding a 3-pt ballast box to the rear of my BX1870 for additional weight for plowing snow. And "yes" it is coming. Inside box is approx. 5 CF. A cubic foot of concrete weights 150#, without splitting hairs. This means concrete would weight 750#, plus box of approx. 100#. 850# total (approx.) Would the BX be able to lift this weight? Should I maybe NOT fill the box completely? Can always add #'s more later. Rear are also filled with WWF. BX spec. suggest it would lift this. Anyone have this setup?