1971 JD 4320 factory yellow Industrial - factory hyd. front-wheel assist, 1 of only 3 made....story here: https://discuss.machinerypete.com/t/rare-1971-john-deere-4320-factory-industrial-yellow-hyd-front-wheel-assist/1179 This 4320 will be at the Classic Green Reunion 2019 event June 13-15 in Grand Island, Neb.