ADDING A SURE GRIP

Troub said
Yep! That’s what this Newport donor 8 3/4 is for. The Newport is donating its 383 motor and 727 trans as well. Will have to get the axle housing shortened.
Got the Newport for $350 so can’t pass up the chance to build up the Dart!

OK, the way I was reading it was you were swapping a sure-grip from the '65 into the existing rear end.

It all makes sense now. BTW, don't be afraid to post any '65 Newport parts on FCBO. You could be doing someone a real favor and recouping your $350.