Well you could always throw an old Scout engine in the back of it for more articulation.
went wheeling with a buddy with one of those toy trucks. Drove straight this steep cat trail with barely a slipping tire. He could absolutely not make it up the hill. He tried fast, slow, the right, middle and left. Finally I backed down to the middle of the hill and asked him if he needed a tow. I think the meant no. So I started back out in the middle of the hill and drove to the top, barely slipping a tire.