I have heard of this and im sure i saw a rear beam at a show a few years ago with a Jag diff on it?
My dad and alot of his mates are all into hot rods and the Jag diff is often used in that scene.
Don't hold me to this but im sure they have said that it is not rated much past 350bhp anyway??
Many are open diffs too, it is the powerlock one you want