the diff cups can also be fixed this way;

First of all this can’t fix diff cups, only prevent them from ever breaking again so you need to start with 4 good diff cups.

Buy a piece of 7/16 diameter brass tubing

cut off 4 pieces that are 1/4 inches long.

Get some aluminum foil, tin foil or some thing that is similar to that.

Cut 4 strips that are 1/4 inch wide and about 6 inches long.

Wrap one strip around a diff cup and take one of the pieces of brass tubing and try to fit it on.

It probably won’t fit so remove one turn of the foil and try again.

Repeat this until the brass piece fits over the foil.

in-case you are wondering, you need the foil because the diff cup is a little smaller than the brass tubing on the inside and the foil takes up that little bit of space.

After the brass piece fits over the diff cup and foil and is not loose, put a couple drops of thin CA glue (tire glue, super glue) on it and let it sit for about 5 minutes while the glue dries completely.

Repeat for the other three diff cups.

The last thing that you need to do is file down the little part of the shock tower that is near the diff cup. This is necessary because the now slightly larger diff cup needs a little more room.