Rear diff problem

A while back I did a differential gear swap and installed a Powertrax diff-lock. And at the tail end of last year it started to make a grinding sound and now it is really bad. I am going to have pull the back cover off and see what the issue is. It also vibrates to car as well. I did some research on the symptoms and it looks like a pinion bearing and it would get to the point of no clearance. 

So now the car is parked until the day we work on it at the shop.