Did all MF-35 in 1961 have the two stage clutches?
Yes, in 1961, when the 35 was re-designated the MF-35, all the “Deluxe” ag models were equipped with dual clutches. It is possible that some 35 “Special” models were still produced and sold in 1961.
These Special models had only two gauges, no “tractormeter” (tachometer), single stage clutches, no live PTO, no live hydraulics, smaller 10″ x 28″ (11.2″ x 28″) rear tires, steel pan seats and steering wheels with exposed metal spokes and no chrome acorn nut.
I believe the industrial versions, the MF-35 Utility and MF-35 Turf tractors were also available with a single stage clutch and no Live PTO or Live Hydraulics. These industrial versions were equipped with foot throttles and available with optional manual shuttle transmissions.