Bell pattern will be different.
"Lima" engines used in mediums would be a source for a bell that would work with your trans. 370s and 429s have the same bell pattern as your 460. According to some posts here, Roadranger 6610 and 6613 were available behind the 370/429s in the early '80s. Also mentioned was an SAE #2 adaptor.
What is the make and model of your trans?