I talked to my clutch guy today and he said that Ford didn't build any 460 manual transmission stuff prior to 1978. He said to convert one you would have to use a flywheel from a FE engine (352, 360, 428...) and a bellhousing for a 351M/400. I remember this swap would usually require 2 separator plates for spacing between the engine/trans. The FE flywheel is 184 T and the late model 460 is 180 T. Ford quit producing the 460 around '79 or '80 and when they started making them again it was a truck only motor. Make sure what year motor you have because the early ones were neutral balanced and the late ones were not. I'm not sure abpout the years on the balance.