There a big difference between the 974 and the earlier 962 cornhead. (I think thats the number) The 962 had the upper drive although I think there was a conversion for them. Also, look at the tin, the 962 snouts have a piano hinge type for narrowing it up, while the 974 has bolt holes and slots. Another big difference is the rollers, with the 962 using a four blade type and the 974 using a much better fluted roller. Yep some of the 974 were a different color yellow.