Re: whats it worth
I wouldn't hazard a guess what it is worth. Whatever you and the seller agree on is the value.
Just a couple of thoughts though. Was it really "rebuilt"? That term is often used loosely. And if it was truly "rebuilt", why did it need rebuilding and by who? True rebuilds only are necessary because of being worn out, burned up, ran without oil, stuff like that.
It was made by Chrysler and is a decent motor, but be aware that they are no longer made and parts are out there but sometimes not easy to find.