hi i just got an Oliver 70 row crop serial # 263264 and i need some info. i wanted to know the difference between an Oliver 70 and a 70 row crop, the tractor i have has white rims front and back original paint on them, who can i tell if it is a six speed i can not tell by shifting, it also as a canvas seat that slips over the two movable seat bars. any other info will help thanks mitch