The ford axles are out of a m80, you may be right potentially respline them, i know obviously he shortens them. This guy is a guru with the mopar stuff as specialises in it. He built my m78 in my ute with a trutrac and its taken a pounding. The main advantage of the m80 axles is all the brake options it gets me that are off the shelf stock items. So keen to get the diff etc in and floor sprayed as will motivate me to get stuck in as its at a bit of a stale mate faze of the build