I like that little machine the only problem with it is rocks float to the surface
While working at the Caterpillar rebuild shop we re worked a 613 self loading scraper to be a rock remover. by stretching the bowl and removing part of the floor of the bowl turning the ejector around to push to the rear and put the door in the rear of the bowl, adding long teeth to the cutting edge constructing a funnel shaped chute for the soil and rocks to be lifted in and a rotating qualifier-drum. The soil and up to quarter sized rocks fell back to the ground anything larger was deposited in the rear of the bowl when full the door raised and the ejector pushed the rocks out. Then sent it to Argentina I don't know how well it worked out but I always thought the concept was beautiful