Whoa. I had to stop reading. Talk about complicated ways to do simple things.
Heath, first caveat, as I said all I know is what I read on the Wikipedia entry for Tartara. It says "iron sand" which to me would mean taconite. Since you have some Yooper ore, I would assume it is hematite. Therefore I would pursue the crucible method.
I've read a little bit about what you guys call crucible steel, like the forum page Son referenced. I get lost in the hobby/craft jargon. The description of the process is basically pack carburizing. You may wnat to search for that. Why anyone would attempt to make steel out of cast iron is beyond me. You could do it out of Ductile Iron though, quite easily actually, well take that back, it's possible. But not out of Gray Iron.