If you don't know how to tear apart an automatic transmission, it would be worth your while to fool around with it and learn. I think there's a couple of web sites that shows a typical breakdown. Then go around to independent repair shops (both general auto and transmission). I've picked up quite a few for free or a couple of dollars. The case is all cast aluminum. If you don't break them down, they go as Irony Aluminum. I don't fool with aluminum motors and let them go as Irony.