I agree with pdentrem. Atlas and Craftsman 10" and 12" lathes all have 3MT spindle, 2MT tailstock ram. Same make 6" lathes are 2MT and 1MT respectively, at least as far as any info I have seen so far.
Gene: I'd sure like to see that exploded view that indicated the 10F spindle is #2 morse. Can you post a copy here?