Eaton 2 speed on the IH. Here's the 2 speed from the 70 IH Loadstar I had. It's most definitely the same 2 speed box but the axle itself seems to be different. For one it has a bolt on inspection cover intead of the solid pumpkin on the Chevy. The picture is all I have of it and it appears to have a loom dropping down so I can't tell what wire goes where from it.
IH Loadstar diff