Front spring hanger and u-bolt plate questions

I'm ditching the stock rear in my '73 Duster, in favor of a yet-to-be acquired 8 3/4.
I'm guessing this will also require new u-bolt plates? I've got a friend that bought the rear for his '67 Barracuda, and now he's thinking he'll need those plates.

Will I need 8 3/4-specific u-bolt plates?

Also, what are you guys using for front spring hangers? I've seen a couple that are beefier, and have an additional mounting hole to lower the rear a little. Anyone have experience with those? Worth it, or just keep the stockers?

I'm going to put in torque boxes and USCar Tool subframe connectors to stiffen up the suspension a bit. Anyone have any thoughts on spring hangers?

-Brad