I don't get all the suggestions of using a torch..... on cast iron!? If the application for the torch is to cut bolts great, otherwise don't waste your time trying. Its all but impossible to cut cast iron with a torch. I use an air-arc unit on iron. The "take it apart the way it went together" suggestion is by far the best, I've beat and cut my way into more trouble trying to save time than I care to remember. Unless you have access to some serious machinery ( read 50k lb excavator) trying to break it apart will probably just turn into frustration. I assume there is an overhead crane in this shop, and even the largest machines rarely have any single casting so big that you couldn't rent a trailer from uhaul and drag her into the yard a piece at a time. Sounds like fun