Cooked the rear in my Dart!

Of all things to go bad, the rear in my 84K mile slant 6 Dart has decided to become a cemet mixer. I drive the damn thing back & forth to work 6 miles in traffic most of the time! Last night it started grinding and holding back. I threw it up on the lift tonight at work and I dropped the driveshaft and spun the rear: it spins freely, then BANG.... binds up. Rotate the pinion backwards 1/4 turn and she's free for another 6-20 spins...than bang, she's tight.

Knowing how EVERYONE swaps out their 7 1/4's for 8 3/4's these things *should* be everywhere. Let's see how long it takes to find one locally....

It' always sumthin.... :-D