The rear input to the diff jumped off and the LF wheel came off at the same time.
Maybe I should use RED Lock-Tite for the in put grub screw?

Also the 2.5 mm cross pins at the outboard drive hub blew off some where. I'll put 2.5 mm roll pins in there,instead!

I used 10 K in the rear diff and 100 K in the front differential and it drove OK,until it fell apart.

It's OK if the wheels fall off,but I don't want those pins to fly off.
https://i.imgur.com/XFj7w49.jpg

When I pulled the diffs apart,there was not much diff fluid inside at all.
I filled them up to the level of the cross pins/spiders.

https://i.imgur.com/6d6aGQ8.jpg