Big Bang Theory, Why is the nose of my Diff pointing straight down...

On some of the 8.25 rears it isn't hard at all to rotate the tube in the housing. I did it with my hot slant six and dropped my driveshaft on the pavement.

Some rear end builders weld the tubes to the housing with nickel rod. Others drill and tap the round holes on either side of the diff and put in plugs that go into the tubes.