U Bolts from a Dakota rear end working on an 8 3/4. Has anyone used this or heard of this.

Well all Aussie mopars had "proper" u bolts
have a set sitting in "rustbuster" as we speak

maybe it was just factories in other lands that did it, or it was a heavy duty or harsh environment option?

read a write up years ago by RE in Mopar Action that covered off the benefits
presumed from that commonplace on 60s-80s mopars

Flat section with a vague waffle pattern on the area around the tube, and a warning in the factory manual about how to torque them and not doing them up too tight.

Dave