I've been thinking of this for awhile. As near as I can see the easiest would be the entire drivetrain from a small Mazda pick up. They made Diesels in the 80s so a rusted out one should be available. I see them advertized in the local rags around here. The problem will be the width of the engine. Most cars these days have Macpherson struts up fron and that allows for alot of engine in the bay. The double wishbone set up in the 120 narrows the possibilities. When Iget aroud to this I will probably want to drop the entire drivetrain in cause all the mixing and matching stuff is just a ppain. Iwould rather follw whatever the engineers thought was the right set up.