My new project . . . I just gotta set this bad boy up

I weighed it and it weighed 10lbs. 15 oz. with batteries controller motor everything. It's pretty light.

I was driving it last night and I flipped it on the street, it rolled for a good 15 feet on the lid and where it came to a stop there was the rear center drive shaft just lying there beside it. ????? I had to take the center diff out to get it back in, I can't figure out how it came out. But that's the only incident I have had while running it.