I can usually slip the cam gear over the cam dowels by hand . There is a slight off set to the cam dowels . The gear can be forced over the dowels wrong so care needs to be taken . I use the hex nut that is listed in Snyders catalog . I don't think that Ford listed torque values for model A bolts or nuts . I think that 100 ft. lbs . torque on the cam nut is a bit excessive . I just use common sense when tightening . Though I have done it before, I don't recommend using a rag between the timing gears to keep them from turning when tightening the cam nut . It is best to remove the side timing cover and use a clamp and wood blocks to hold the cam gear from turning . The rag method puts strain on the gear teeth . If the rag method is used with a fiber cam gear , the gear usually fails quickly . For longer timing gear life , I prefer to use either the bronze or aluminum cam gear .