Help with Axle Housing Identification

I have an 8 3/4 housing that I can't identify.
It measures roughly 59 1/8 from end-to-end (bare housing). Based on the axle info found here Mopar Casting Numbers - MyMopar.com - Mopar Part Numners and Mopar Rear Axle Dimensions , I can't find anything with a 59 1/8" width. The spring perches are on the top of the housing, which should mean that it's out of a truck. Also, the spring perches are only 43" center-to-center (which would fit an A-body), and there is no sign that they've ever been moved.

Any ideas?

Thanks,
Gabe