71 Demon Back From The Dead

Kern Dog said
The 68-70 B housing is 3 inches wider in total from what I recall.

Yep, you're spot on.

Mopar Rear Axle Dimensions

Perfect for a Demon/Duster.....standard Rallye wheels are pushed outwards and fill the wheel wells nicely. Not so good for wide Torq Thrusts though, unless you pay big money for a custom offset.