the front four link had a performance advantage in that it made it work in a similar way to the rear to plant more power, but the extra wieght needed due having top put a small cradle on the front, and the advent of fs, which would cause the front to slam in the ground made these designs go the way of the dinosaurs, the frame in the second pic is guy woods, which at one point ran as hulk, him and the hall brothers ran the bulldozer name when they were both sponsored by smokecraft until pace bought the name and asked tom meents to run it on his chassis, i am guessing feld asked guy to run it on his chassis, until meents hired him and put him in his old wilman chassis