Steering Box Identification

The dirty box is out of a 73 Duster. The clean one is what I need help ID'ing.

The spline on the clean box is a larger diameter. Notice that the filler plug is in a different location & the cover is a different shape & rotated.

042700_1658[00].jpg042700_1700[00].jpg

042700_1658[00].jpg

042700_1700[00].jpg