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

What's "proper"? Flat insides around the bend because you think it is "proper"? I've torn down a LOT of original suspension Mopars and not one single one ever had the flats around the inside of the u bolt bends. Not one. In fact, I've never in my life even seen it on any muscle car era Mopar I've ever been under.