Sorry that I didn't get back sooner, but I haven't been on PriusChat for quite awhile. It is an AZ600 just like the one I drove in the late 70s. I did have to rebuild the engine once, replacing the crankshaft and cam shaft, but it was pretty easy the way the engine could stay connected to the subframe and be lowered out of the chasis. It was a lot of fun to drive around and pretty easy to work on. I really enjoyed that car which is probably why I chose that picture for my Avatar. It beats having a picture of a cat.